Don't replace environment variables and system properties in get table configs REST API

[yashmayya]

• Fixes Environment variables in table configs are revealed #13983
• When the table configs are stored in ZK, the environment variables and system properties are stored as is (i.e., without replacing with actual values).
• However, the table config retrieval REST APIs use an internal ZK metadata API that replaces these variables with their actual values for use internally within Pinot.
• This shouldn't be the case for the user facing REST API since these values could contain secrets.

[codecov-commenter]

Codecov Report

Attention: Patch coverage is 18.75000% with 13 lines in your changes missing coverage. Please review.

Project coverage is 57.91%. Comparing base (59551e4) to head (c9da03b).
Report is 1037 commits behind head on master.

Files with missing lines	Patch %	Lines
...ache/pinot/common/metadata/ZKMetadataProvider.java	0.00%	10 Missing ⚠️
...ntroller/helix/core/PinotHelixResourceManager.java	25.00%	3 Missing ⚠️

Additional details and impacted files

@@             Coverage Diff              @@
##             master   #14002      +/-   ##
============================================
- Coverage     61.75%   57.91%   -3.84%     
- Complexity      207      219      +12     
============================================
  Files          2436     2613     +177     
  Lines        133233   143278   +10045     
  Branches      20636    21996    +1360     
============================================
+ Hits          82274    82976     +702     
- Misses        44911    53812    +8901     
- Partials       6048     6490     +442     

Flag	Coverage Δ
custom-integration1	<0.01% <0.00%> (-0.01%)	⬇️
integration	<0.01% <0.00%> (-0.01%)	⬇️
integration1	<0.01% <0.00%> (-0.01%)	⬇️
integration2	0.00% <0.00%> (ø)
java-11	57.86% <18.75%> (-3.85%)	⬇️
java-21	57.78% <18.75%> (-3.84%)	⬇️
skip-bytebuffers-false	57.90% <18.75%> (-3.85%)	⬇️
skip-bytebuffers-true	57.74% <18.75%> (+30.01%)	⬆️
temurin	57.91% <18.75%> (-3.84%)	⬇️
unittests	57.90% <18.75%> (-3.84%)	⬇️
unittests1	40.71% <0.00%> (-6.18%)	⬇️
unittests2	27.97% <18.75%> (+0.24%)	⬆️

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