Backport of Update base ref property name into release/1.15.x

[hc-github-team-consul-core]

Backport

This PR is auto-generated from #18851 to be assessed for backporting due to the inclusion of the label backport/1.15.

🚨

Warning automatic cherry-pick of commits failed. If the first commit failed,
you will see a blank no-op commit below. If at least one commit succeeded, you
will see the cherry-picked commits up to, not including, the commit where
the merge conflict occurred.

The person who merged in the original PR is:
@NiniOak
This person should manually cherry-pick the original PR into a new backport PR,
and close this one when the manual backport PR is merged in.

merge conflict error: POST https://api.github.com/repos/hashicorp/consul/merges: 409 Merge conflict []

The below text is copied from the body of the original PR.

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Description

PROBLEM
We found a bug where on pull request merge, the following error was returned by the filter_changed_files_go_test.sh

fatal: ambiguous argument 'origin/': unknown revision or path not in the working tree.
Use '--' to separate paths from revisions, like this:
'git <command> [<revision>...] -- [<file>...]'

See example here

SOLUTION
Update the conditional-skip job with a step to conditional check the github event,

• if event is pull_request merged, set GitHub branch value to github.ref_name
• for pull_request event, set GitHub branch value to github.head_ref
  Update the filter_changed_files_go_test.sh script to fail on script error and set the default behaviour to trigger CI, the previous behaviour was to skip CI.

Testing & Reproduction steps

CI skipping tests where all changes are from skipped directories
CI running test workflows by default

Links

PR Checklist

• updated test coverage
• external facing docs updated
• appropriate backport labels added
• not a security concern

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Overview of commits

• a7fbd6b - adb87b7 - 43839f7

[hashicorp-cla]

All committers have signed the CLA.

[github-team-consul-core-pr-approver]

Auto approved Consul Bot automated PR