pathschanged info is included for new tag push event

[saumdh]

Describe the bug

When a new tag is pushed, it sends the 'ref' data (refs/tags/...) which makes sense. But there is also a pathschanged flag based on the last PR which does not make sense as the new tag build is for all PR's since the last build.

Steps to reproduce

1. Try a build which has new tag push and pathschanged condition evaluating as false. The build goes thru.
2. Now have a new tag push with pathschanged condition evaluating as true. The build does not go thru even if there are multiple PR's in between but pathschanged evaluation only looks at the last PR.

Expected behavior

pathschanged should not be checked for new tag push event.

So, build should go thru for #2 in the above example.

Additional context

Following logs were observed:
{"build_after":"e8bfa225210103b8f1eb5579d78729d9acaef2d6","build_before":"0000000000000000000000000000000000000000","level":"info","msg":"a path field was seen","repo_name":"logistics-dynamic-pricing","repo_namespace":"deliveryhero","time":"2023-04-24T12:18:21Z"}
{"build_after":"e8bfa225210103b8f1eb5579d78729d9acaef2d6","build_before":"0000000000000000000000000000000000000000","level":"info","msg":"excluding pipeline DPS Build","repo_name":"logistics-dynamic-pricing","repo_namespace":"deliveryhero","time":"2023-04-24T12:18:21Z"}