[Go SDK] Exec changes for timer support

[riteshghorse]

This PR adds changes to exec package without fn-invocation part
Part of #22737

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[riteshghorse]

stop reviewer notifications

[github-actions]

Stopping reviewer notifications for this pull request: requested by reviewer

[codecov]

Codecov Report

Merging #24692 (bd700d8) into master (aa6cc16) will increase coverage by 0.10%.
The diff coverage is 55.35%.

@@            Coverage Diff             @@
##           master   #24692      +/-   ##
==========================================
+ Coverage   73.34%   73.44%   +0.10%     
==========================================
  Files         719      752      +33     
  Lines       97169   102380    +5211     
==========================================
+ Hits        71268    75196    +3928     
- Misses      24552    25715    +1163     
- Partials     1349     1469     +120     

Flag	Coverage Δ
go	55.11% <55.35%> (+3.53%)	⬆️

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ
sdks/go/pkg/beam/core/runtime/exec/data.go	0.00% <ø> (ø)
sdks/go/pkg/beam/core/runtime/exec/translate.go	23.14% <0.00%> (+5.94%)	⬆️
sdks/go/pkg/beam/core/runtime/exec/timers.go	41.07% <41.07%> (ø)
sdks/go/pkg/beam/core/runtime/exec/pardo.go	60.07% <100.00%> (+0.47%)	⬆️
sdks/go/pkg/beam/core/timers/timers.go	100.00% <100.00%> (ø)

... and 62 files with indirect coverage changes

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[github-actions]

This pull request has been marked as stale due to 60 days of inactivity. It will be closed in 1 week if no further activity occurs. If you think that’s incorrect or this pull request requires a review, please simply write any comment. If closed, you can revive the PR at any time and @mention a reviewer or discuss it on the dev@beam.apache.org list. Thank you for your contributions.

[github-actions]

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