cmd/go: remove --first-parent for git tag discovery

[saschagrunert]

This commit fixes an invalid last tag retrieval for go modules by
including git tag from merge branches.

Fixes #31673

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This PR (HEAD: 0c0e484) has been imported to Gerrit for code review.

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Message from Pontus Leitzler:

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(1 comment)

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Message from Sascha Grunert:

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Patch Set 1:

(1 comment)

It depends on the release strategy of the related project. If the release branch gets merged back then this fix works as intended. If the project does not merge back the release branch then the tags won't be considered. This is out of scope of this fix and would imply further changes.

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Message from Sascha Grunert:

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(1 comment)

I mean we could also choose the very latest tag by checking all branches like this:

git describe --tags $(git rev-list --tags --max-count=1)

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Message from thepudds:

Patch Set 1:

This is not a comment on any of the proposed approaches, but just wanted to make a quick general comment that elsewhere the go tool tries to be careful about what versions it pulls in. See for example
#27043 (comment) or #27191 (comment).

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Message from Jay Conrod:

Patch Set 1:

Thanks for reporting this issue and working on a fix. We ended up merging CL 174061 to solve this (thanks Pontus Leitzler and thepudds!).

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This PR is being closed because golang.org/cl/173667 has been abandoned.

Issue resolved by CL 174061