[#31991][prism] Allow Empty Composites

[lostluck]

Allows composites that only do SDK Side PCollection graph manipulation.

These composites have no payload, or subtransforms, so there's nothing for a runner to do with
them for execution. Simply ignore them.

This allows 3 Java validates runner tests in PipelineTest to pass: testIdentityTransform, testTupleProjectionTransform, and testTupleInjectionTransform.

Fixes #31991

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[codecov]

Codecov Report

Attention: Patch coverage is 0% with 7 lines in your changes missing coverage. Please review.

Project coverage is 56.91%. Comparing base (ffae5b5) to head (7eb43fe).
Report is 12 commits behind head on master.

Files	Patch %	Lines
...m/runners/prism/internal/jobservices/management.go	0.00%	7 Missing ⚠️

Additional details and impacted files

@@             Coverage Diff              @@
##             master   #32024      +/-   ##
============================================
- Coverage     56.92%   56.91%   -0.01%     
  Complexity     1474     1474              
============================================
  Files           961      961              
  Lines        151462   151469       +7     
  Branches       1076     1076              
============================================
- Hits          86215    86213       -2     
- Misses        63065    63071       +6     
- Partials       2182     2185       +3     

Flag	Coverage Δ
go	34.60% <0.00%> (+<0.01%)	⬆️

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[lostluck]

R: @damondouglas

We don't allow expressing this in the Go SDK so no coverage is possible here. Covered by the Java tests.

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