[ci] Fix binary-size-check workflow

[chahatsagarmain]

Which problem is this PR solving?

• Fix for one issue caused in Add CI workflow to guard against increases in the binary size #6527

Description of the changes

• cache_output not being set after a cache hit using restore key
• Instead check for cache-matched-key != ''"

How was this change tested?

Checklist

• I have read https://github.com/jaegertracing/jaeger/blob/master/CONTRIBUTING_GUIDELINES.md
• I have signed all commits
• I have added unit tests for the new functionality
• I have run lint and test steps successfully
  • for jaeger: make lint test
  • for jaeger-ui: npm run lint and npm run test

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 96.25%. Comparing base (2ee8e4c) to head (f87ad3e).
Report is 4 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #6552      +/-   ##
==========================================
- Coverage   96.26%   96.25%   -0.02%     
==========================================
  Files         372      372              
  Lines       21371    21371              
==========================================
- Hits        20573    20570       -3     
- Misses        608      610       +2     
- Partials      190      191       +1     

Flag	Coverage Δ
badger_v1	10.65% <ø> (ø)
badger_v2	2.78% <ø> (ø)
cassandra-4.x-v1-manual	16.55% <ø> (ø)
cassandra-4.x-v2-auto	2.71% <ø> (ø)
cassandra-4.x-v2-manual	2.71% <ø> (ø)
cassandra-5.x-v1-manual	16.55% <ø> (ø)
cassandra-5.x-v2-auto	2.71% <ø> (ø)
cassandra-5.x-v2-manual	2.71% <ø> (ø)
elasticsearch-6.x-v1	20.34% <ø> (ø)
elasticsearch-7.x-v1	20.40% <ø> (ø)
elasticsearch-8.x-v1	20.57% <ø> (+<0.01%)	⬆️
elasticsearch-8.x-v2	2.77% <ø> (ø)
grpc_v1	12.16% <ø> (ø)
grpc_v2	9.04% <ø> (ø)
kafka-3.x-v1	10.33% <ø> (ø)
kafka-3.x-v2	2.78% <ø> (ø)
memory_v2	2.78% <ø> (ø)
opensearch-1.x-v1	20.45% <ø> (-0.01%)	⬇️
opensearch-2.x-v1	20.45% <ø> (-0.01%)	⬇️
opensearch-2.x-v2	2.77% <ø> (-0.01%)	⬇️
tailsampling-processor	0.51% <ø> (ø)
unittests	95.13% <ø> (-0.02%)	⬇️

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