Add a workaround for BEAM-20873 for optimized list side inputs.

[robertwb]

This triggered a case with Dataflow Runner v1 and PTransformOverrides that exposed https://github.com/apache/beam/issues/20873 .

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[robertwb]

R: @abacn

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[Abacn]

Looks like cacheCandidatesUpdaterTest (org.apache.beam.runners.spark.CacheTest) failed in 2 attempts.

[Abacn]

THe failing test is caused by this PR. After merged java precommit is red on master branch, and the same failure see in other PRs (e.g. #31175: https://github.com/apache/beam/actions/runs/8943529889/job/24568447748?pr=31175)

I checked locally that it fails on latest master

cacheCandidatesUpdaterTest
java.lang.AssertionError: expected:<2> but was:<3>
	at org.junit.Assert.fail(Assert.java:89)
	at org.junit.Assert.failNotEquals(Assert.java:835)

and passes when reverting this PR

$ git checkout HEAD^
$ ./gradlew :runners:spark:3:test --tests org.apache.beam.runners.spark.CacheTest

get

Tests Standard error
Test	Duration	Result
cacheCandidatesUpdaterTest	0.333s	passed
shouldCacheTest	1.137s	passed

[robertwb]

Does anyone know what this test is trying to verify? It does look related, but it also looks like it might be a change detector test.

[robertwb]

https://github.com/apache/beam/pull/31184