Use FrozenSet in two appropriate places

[joegoldman2]

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Summary of the changes (Less than 80 chars)

Description

Convert two static HashSet on which only read operations are performed to FrozenSet.

Benchmark result:

Method	Mean	Error	StdDev
HashSetContains	9.388 ns	0.1441 ns	0.1348 ns
FrozenSetContains	6.786 ns	0.1620 ns	0.1515 ns

Benchmark code

using System.Collections.Frozen;
using BenchmarkDotNet.Attributes;
using BenchmarkDotNet.Running;

BenchmarkRunner.Run<Tests>();

public class Tests
{
    public static HashSet<string> OpenIdProviderMetadataNamesUpperCase = new HashSet<string>
    {
        "ACR_VALUES_SUPPORTED",
        "AUTHORIZATION_ENDPOINT",
        "AUTHORIZATION_RESPONSE_ISS_PARAMETER_SUPPORTED",
        "BACKCHANNEL_AUTHENTICATION_ENDPOINT",
        "BACKCHANNEL_AUTHENTICATION_REQUEST_SIGNING_ALG_VALUES_SUPPORTED",
        "BACKCHANNEL_TOKEN_DELIVERY_MODES_SUPPORTED",
        "BACKCHANNEL_USER_CODE_PARAMETER_SUPPORTED",
        "CHECK_SESSION_IFRAME",
        "CLAIMS_LOCALES_SUPPORTED",
        "CLAIMS_PARAMETER_SUPPORTED",
        "CLAIMS_SUPPORTED",
        "CLAIM_TYPES_SUPPORTED",
        "CODE_CHALLENGE_METHODS_SUPPORTED",
        ".WELL-KNOWN/OPENID-CONFIGURATION",
        "DEVICE_AUTHORIZATION_ENDPOINT",
        "DISPLAY_VALUES_SUPPORTED",
        "DPOP_SIGNING_ALG_VALUES_SUPPORTED",
        "END_SESSION_ENDPOINT",
        "FRONTCHANNEL_LOGOUT_SESSION_SUPPORTED",
        "FRONTCHANNEL_LOGOUT_SUPPORTED",
        "HTTP_LOGOUT_SUPPORTED",
        "GRANT_TYPES_SUPPORTED",
        "ID_TOKEN_ENCRYPTION_ALG_VALUES_SUPPORTED",
        "ID_TOKEN_ENCRYPTION_ENC_VALUES_SUPPORTED",
        "ID_TOKEN_SIGNING_ALG_VALUES_SUPPORTED",
        "INTROSPECTION_ENDPOINT",
        "INTROSPECTION_ENDPOINT_AUTH_METHODS_SUPPORTED",
        "INTROSPECTION_ENDPOINT_AUTH_SIGNING_ALG_VALUES_SUPPORTED",
        "JWKS_URI",
        "ISSUER",
        "LOGOUT_SESSION_SUPPORTED",
        "OP_POLICY_URI",
        "OP_TOS_URI",
        "PROMPT_VALUES_SUPPORTED",
        "PUSHED_AUTHORIZATION_REQUEST_ENDPOINT",
        "REGISTRATION_ENDPOINT",
        "REQUEST_OBJECT_ENCRYPTION_ALG_VALUES_SUPPORTED",
        "REQUEST_OBJECT_ENCRYPTION_ENC_VALUES_SUPPORTED",
        "REQUEST_OBJECT_SIGNING_ALG_VALUES_SUPPORTED",
        "REQUEST_PARAMETER_SUPPORTED",
        "REQUEST_URI_PARAMETER_SUPPORTED",
        "REQUIRE_PUSHED_AUTHORIZATION_REQUESTS",
        "REQUIRE_REQUEST_URI_REGISTRATION",
        "RESPONSE_MODES_SUPPORTED",
        "RESPONSE_TYPES_SUPPORTED",
        "REVOCATION_ENDPOINT",
        "REVOCATION_ENDPOINT_AUTH_METHODS_SUPPORTED",
        "REVOCATION_ENDPOINT_AUTH_SIGNING_ALG_VALUES_SUPPORTED",
        "SERVICE_DOCUMENTATION",
        "SCOPES_SUPPORTED",
        "SUBJECT_TYPES_SUPPORTED",
        "TOKEN_ENDPOINT",
        "TOKEN_ENDPOINT_AUTH_METHODS_SUPPORTED",
        "TOKEN_ENDPOINT_AUTH_SIGNING_ALG_VALUES_SUPPORTED",
        "UI_LOCALES_SUPPORTED",
        "USERINFO_ENDPOINT",
        "USERINFO_ENCRYPTION_ALG_VALUES_SUPPORTED",
        "USERINFO_ENCRYPTION_ENC_VALUES_SUPPORTED",
        "USERINFO_SIGNING_ALG_VALUES_SUPPORTED",
    };

    public static readonly FrozenSet<string> OpenIdProviderMetadataNamesUpperCaseFrozenSet = new HashSet<string>
    {
        "ACR_VALUES_SUPPORTED",
        "AUTHORIZATION_ENDPOINT",
        "AUTHORIZATION_RESPONSE_ISS_PARAMETER_SUPPORTED",
        "BACKCHANNEL_AUTHENTICATION_ENDPOINT",
        "BACKCHANNEL_AUTHENTICATION_REQUEST_SIGNING_ALG_VALUES_SUPPORTED",
        "BACKCHANNEL_TOKEN_DELIVERY_MODES_SUPPORTED",
        "BACKCHANNEL_USER_CODE_PARAMETER_SUPPORTED",
        "CHECK_SESSION_IFRAME",
        "CLAIMS_LOCALES_SUPPORTED",
        "CLAIMS_PARAMETER_SUPPORTED",
        "CLAIMS_SUPPORTED",
        "CLAIM_TYPES_SUPPORTED",
        "CODE_CHALLENGE_METHODS_SUPPORTED",
        ".WELL-KNOWN/OPENID-CONFIGURATION",
        "DEVICE_AUTHORIZATION_ENDPOINT",
        "DISPLAY_VALUES_SUPPORTED",
        "DPOP_SIGNING_ALG_VALUES_SUPPORTED",
        "END_SESSION_ENDPOINT",
        "FRONTCHANNEL_LOGOUT_SESSION_SUPPORTED",
        "FRONTCHANNEL_LOGOUT_SUPPORTED",
        "HTTP_LOGOUT_SUPPORTED",
        "GRANT_TYPES_SUPPORTED",
        "ID_TOKEN_ENCRYPTION_ALG_VALUES_SUPPORTED",
        "ID_TOKEN_ENCRYPTION_ENC_VALUES_SUPPORTED",
        "ID_TOKEN_SIGNING_ALG_VALUES_SUPPORTED",
        "INTROSPECTION_ENDPOINT",
        "INTROSPECTION_ENDPOINT_AUTH_METHODS_SUPPORTED",
        "INTROSPECTION_ENDPOINT_AUTH_SIGNING_ALG_VALUES_SUPPORTED",
        "JWKS_URI",
        "ISSUER",
        "LOGOUT_SESSION_SUPPORTED",
        "OP_POLICY_URI",
        "OP_TOS_URI",
        "PROMPT_VALUES_SUPPORTED",
        "PUSHED_AUTHORIZATION_REQUEST_ENDPOINT",
        "REGISTRATION_ENDPOINT",
        "REQUEST_OBJECT_ENCRYPTION_ALG_VALUES_SUPPORTED",
        "REQUEST_OBJECT_ENCRYPTION_ENC_VALUES_SUPPORTED",
        "REQUEST_OBJECT_SIGNING_ALG_VALUES_SUPPORTED",
        "REQUEST_PARAMETER_SUPPORTED",
        "REQUEST_URI_PARAMETER_SUPPORTED",
        "REQUIRE_PUSHED_AUTHORIZATION_REQUESTS",
        "REQUIRE_REQUEST_URI_REGISTRATION",
        "RESPONSE_MODES_SUPPORTED",
        "RESPONSE_TYPES_SUPPORTED",
        "REVOCATION_ENDPOINT",
        "REVOCATION_ENDPOINT_AUTH_METHODS_SUPPORTED",
        "REVOCATION_ENDPOINT_AUTH_SIGNING_ALG_VALUES_SUPPORTED",
        "SERVICE_DOCUMENTATION",
        "SCOPES_SUPPORTED",
        "SUBJECT_TYPES_SUPPORTED",
        "TOKEN_ENDPOINT",
        "TOKEN_ENDPOINT_AUTH_METHODS_SUPPORTED",
        "TOKEN_ENDPOINT_AUTH_SIGNING_ALG_VALUES_SUPPORTED",
        "UI_LOCALES_SUPPORTED",
        "USERINFO_ENDPOINT",
        "USERINFO_ENCRYPTION_ALG_VALUES_SUPPORTED",
        "USERINFO_ENCRYPTION_ENC_VALUES_SUPPORTED",
        "USERINFO_SIGNING_ALG_VALUES_SUPPORTED",
    }.ToFrozenSet();

    [Benchmark]
    public bool HashSetContains()
    {
        return OpenIdProviderMetadataNamesUpperCase.Contains("INTROSPECTION_ENDPOINT");
    }

    [Benchmark]
    public bool FrozenSetContains()
    {
        return OpenIdProviderMetadataNamesUpperCaseFrozenSet.Contains("INTROSPECTION_ENDPOINT");
    }
}

[jennyf19]

thanks again @joegoldman2 for the contribution