[BEAM-3304] documentation for PaneInfo in BPG

[riteshghorse]

Update Beam Programming guide to reflect usage of PaneInfo for Go SDK.

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[codecov]

Codecov Report

Merging #17047 (4fc996a) into master (95a5c26) will increase coverage by 0.00%.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master   #17047   +/-   ##
=======================================
  Coverage   73.75%   73.76%           
=======================================
  Files         667      667           
  Lines       87406    87406           
=======================================
+ Hits        64468    64473    +5     
+ Misses      21831    21826    -5     
  Partials     1107     1107           

Flag	Coverage Δ
go	48.93% <ø> (ø)

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

Impacted Files	Coverage Δ
sdks/go/pkg/beam/forward.go	40.00% <ø> (ø)
.../python/apache_beam/transforms/periodicsequence.py	96.72% <0.00%> (-1.64%)	⬇️
...ks/python/apache_beam/runners/worker/sdk_worker.py	89.06% <0.00%> (+0.15%)	⬆️
sdks/python/apache_beam/internal/metrics/metric.py	91.00% <0.00%> (+1.00%)	⬆️
...che_beam/runners/interactive/interactive_runner.py	92.75% <0.00%> (+1.44%)	⬆️
.../python/apache_beam/testing/test_stream_service.py	93.02% <0.00%> (+4.65%)	⬆️

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[damccorm]

Request as a reviewer - in the future for website changes, could you please link to the rendered website page that you're modifying, or take a screenshot if its a small change? Website_Stage_GCS automatically publishes a version, you can find the link in the CI build (in this case its http://apache-beam-website-pull-requests.storage.googleapis.com/17047/documentation/programming-guide/index.html#other-dofn-parameters). Personally, I like embedding a screenshot in the description even more so there's no link following needed

[damccorm]

Nice! LGTM

[damccorm]

R: @youngoli - looks like the bot still can't authenticate 😢 so requesting final approval didn't work

[github-actions]

Stopping reviewer notifications for this pull request: review requested by someone other than the bot, ceding control

[youngoli]

This looks mostly good to me, except I think the changes to Beam itself should go in a separate PR and the website changes should be submitted once the feature is available in a current release (so we should wait a little if this is coming in 2.38).

Ritesh, can you create a new PR with just the changes in pkg/beam and test/integration? That one should be a quick review & merge from me.

[riteshghorse]

The pane observation is available in 2.37.0 but I didn't submit the documentation at that time. So I think this should be good to merge.

[riteshghorse]

R: @lostluck

[lostluck]

LGTM! Thanks Ritesh :D

https://apache-beam-website-pull-requests.storage.googleapis.com/17047/documentation/programming-guide/index.html#other-dofn-parameters