docs: generate sample code in the Java microgenerator

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PiperOrigin-RevId: 356341083
Source-Link: googleapis/googleapis@8d8c008

[codecov]

Codecov Report

Merging #498 (b56be2f) into master (d089a0b) will not change coverage.
The diff coverage is n/a.

@@ Coverage Diff @@ ## master #498 +/- ## ========================================= Coverage 75.38% 75.38% + Complexity 761 760 -1  ========================================= Files 129 129 Lines 3875 3875 Branches 173 174 +1 ========================================= Hits 2921 2921 Misses 850 850 Partials 104 104 

Impacted Files	Coverage Δ	Complexity Δ
...google/cloud/pubsublite/v1/AdminServiceClient.java	91.37% <ø> (ø)	55.00 <0.00> (ø)
...oogle/cloud/pubsublite/v1/CursorServiceClient.java	82.00% <ø> (ø)	14.00 <0.00> (ø)
...ubsublite/v1/PartitionAssignmentServiceClient.java	34.78% <ø> (ø)	4.00 <0.00> (ø)
...le/cloud/pubsublite/v1/PublisherServiceClient.java	34.78% <ø> (ø)	4.00 <0.00> (ø)
...e/cloud/pubsublite/v1/SubscriberServiceClient.java	34.78% <ø> (ø)	4.00 <0.00> (ø)
...e/cloud/pubsublite/v1/TopicStatsServiceClient.java	69.23% <ø> (ø)	10.00 <0.00> (ø)

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