dhcp: T5840: Merge systemd service overrides for kea-ctrl-agent

[indrajitr]

Change summary

Default systemd service for kea-ctrl-agent expects /etc/kea/kea-api-password which is not used in VyOS.

The systemd unit override to remove the condition does not need to be in a separate (templated and dynamic) override file and can be merged into the existing static override file.

This is a modification of #2676 to achieve the same outcome.

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Code style update (formatting, renaming)
• Refactoring (no functional changes)
• Migration from an old Vyatta component to vyos-1x, please link to related PR inside obsoleted component
• Other (please describe):

Related Task(s)

Related PR(s)

#2676

How to test / Smoketest result

vyos@test-0115:~$ /usr/libexec/vyos/tests/smoke/cli/test_service_dhcp-server.py 
test_dhcp_exclude_in_range (__main__.TestServiceDHCPServer.test_dhcp_exclude_in_range) ... ok
test_dhcp_exclude_not_in_range (__main__.TestServiceDHCPServer.test_dhcp_exclude_not_in_range) ... ok
test_dhcp_high_availability (__main__.TestServiceDHCPServer.test_dhcp_high_availability) ... ok
test_dhcp_high_availability_standby (__main__.TestServiceDHCPServer.test_dhcp_high_availability_standby) ... ok
test_dhcp_multiple_pools (__main__.TestServiceDHCPServer.test_dhcp_multiple_pools) ... ok
test_dhcp_on_interface_with_vrf (__main__.TestServiceDHCPServer.test_dhcp_on_interface_with_vrf) ... ok
test_dhcp_relay_server (__main__.TestServiceDHCPServer.test_dhcp_relay_server) ... ok
test_dhcp_single_pool_options (__main__.TestServiceDHCPServer.test_dhcp_single_pool_options) ... ok
test_dhcp_single_pool_options_scoped (__main__.TestServiceDHCPServer.test_dhcp_single_pool_options_scoped) ... ok
test_dhcp_single_pool_range (__main__.TestServiceDHCPServer.test_dhcp_single_pool_range) ... ok
test_dhcp_single_pool_static_mapping (__main__.TestServiceDHCPServer.test_dhcp_single_pool_static_mapping) ...ok

----------------------------------------------------------------------
Ran 11 tests in 332.104s

OK

Checklist:

• I have read the CONTRIBUTING document
• I have linked this PR to one or more Phabricator Task(s)
• I have run the components SMOKETESTS if applicable
• My commit headlines contain a valid Task id
• My change requires a change to the documentation
• I have updated the documentation accordingly

[github-actions]

👍
No issues in PR Title / Commit Title

[github-actions]

CI integration 👍 passed!

Details

CI logs

• CLI Smoketests (no interfaces) 👍 passed
• CLI Smoketests (interfaces only) 👍 passed
• Config tests 👍 passed
• RAID1 tests 👍 passed
• TPM tests 👍 passed