Add authzHandler to sdk-validator's grpc server

[hasit]

Description of change

Add authzHandler to sdk-validator's grpc server

• Add CommonHandler
• Refactor FlowControlHandler with CommonHandler

Checklist

• Tested in playground or other setup
• Documentation is changed or added
• Tests and/or benchmarks are included
• Breaking changes

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This change is 

[codecov]

Codecov Report

Base: 37.61% // Head: 37.54% // Decreases project coverage by -0.07% ⚠️

Coverage data is based on head (56b5547) compared to base (993ccc8).
Patch coverage: 0.00% of modified lines in pull request are covered.

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #797      +/-   ##
==========================================
- Coverage   37.61%   37.54%   -0.08%     
==========================================
  Files         285      286       +1     
  Lines       20819    20852      +33     
==========================================
- Hits         7831     7828       -3     
- Misses      12506    12541      +35     
- Partials      482      483       +1     

Impacted Files	Coverage Δ
cmd/sdk-validator/main.go	1.40% <0.00%> (-0.20%)	⬇️
cmd/sdk-validator/validator/common.go	0.00% <0.00%> (ø)
cmd/sdk-validator/validator/flowcontrol.go	0.00% <0.00%> (ø)
cmd/sdk-validator/validator/trace.go	0.00% <0.00%> (ø)
pkg/jobs/job.go	80.62% <0.00%> (-2.33%)	⬇️

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[tanveergill]

@hasit,
What’s this blocked on? Please try to get this to completion