Fix containValue serialization

[jto]

No description provided.

[codecov]

Codecov Report

Merging #3128 into master will decrease coverage by 0.03%.
The diff coverage is 55.55%.

@@            Coverage Diff             @@
##           master    #3128      +/-   ##
==========================================
- Coverage   73.05%   73.01%   -0.04%     
==========================================
  Files         232      232              
  Lines        7607     7613       +6     
  Branches      343      335       -8     
==========================================
+ Hits         5557     5559       +2     
- Misses       2050     2054       +4     

Impacted Files	Coverage Δ
.../smb/syntax/SortMergeBucketSCollectionSyntax.scala	42.85% <0.00%> (-57.15%)	⬇️
.../main/scala/com/spotify/scio/testing/JobTest.scala	88.15% <100.00%> (ø)
...com/spotify/scio/testing/SCollectionMatchers.scala	96.37% <100.00%> (+0.05%)	⬆️
...main/scala/com/spotify/scio/values/SideInput.scala	95.45% <0.00%> (-4.55%)	⬇️
...scala/com/spotify/scio/extra/sparkey/package.scala	75.00% <0.00%> (-1.14%)	⬇️
...y/scio/values/PairSkewedSCollectionFunctions.scala	94.28% <0.00%> (+2.85%)	⬆️

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