fix: External secrets from vault (#297)

This should fix that secrets failed to be populated from vault by kubernetes-external-secrets. The log of kubernetes-external-secrets showed errors like:
{"level":50,"time":1630943166224,"pid":17,"hostname":"kubernetes-external-secrets-7686994b8c-ldrwh","payload":{"response":{"statusCode":400,"body":{"errors":["invalid role name \"jx-vault\""]}}},"msg":"failure while polling the secret jx/lighthouse-hmac-token"}

modules/vault/charts.tf

@@ -14,6 +14,6 @@ resource "helm_release" "vault-instance" {
   chart      = "vault-instance"
   namespace  = "jx-vault"
   repository = "https://jenkins-x-charts.github.io/repo"
-  version    = "1.0.20"
+  version    = "1.0.21"
   depends_on = [helm_release.vault-operator]
 }