Improve JSON_EXTRACT_SCALAR error message

[Jackie-Jiang]

Return proper error message when json path is not valid

[codecov-commenter]

Codecov Report

Merging #10176 (ee5a47c) into master (28b3d3e) will decrease coverage by 9.15%.
The diff coverage is 77.77%.

@@             Coverage Diff              @@
##             master   #10176      +/-   ##
============================================
- Coverage     70.43%   61.29%   -9.15%     
+ Complexity     5802     4990     -812     
============================================
  Files          2018     2006      -12     
  Lines        108987   108637     -350     
  Branches      16539    16501      -38     
============================================
- Hits          76763    66585   -10178     
- Misses        26847    37080   +10233     
+ Partials       5377     4972     -405     

Flag	Coverage Δ
integration1	24.72% <66.66%> (+<0.01%)	⬆️
integration2	?
unittests1	67.85% <77.77%> (+0.01%)	⬆️
unittests2	?

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ
...m/function/JsonExtractScalarTransformFunction.java	54.75% <77.77%> (-0.22%)	⬇️
...pinot/core/data/manager/realtime/TimerService.java	0.00% <0.00%> (-100.00%)	⬇️
...t/core/plan/StreamingInstanceResponsePlanNode.java	0.00% <0.00%> (-100.00%)	⬇️
...pinot/controller/recommender/io/ConfigManager.java	0.00% <0.00%> (-100.00%)	⬇️
...ore/operator/streaming/StreamingResponseUtils.java	0.00% <0.00%> (-100.00%)	⬇️
.../org/apache/pinot/client/AggregationResultSet.java	0.00% <0.00%> (-100.00%)	⬇️
...ntroller/recommender/rules/impl/JsonIndexRule.java	0.00% <0.00%> (-100.00%)	⬇️
...troller/recommender/io/metadata/FieldMetadata.java	0.00% <0.00%> (-100.00%)	⬇️
...roller/recommender/rules/impl/BloomFilterRule.java	0.00% <0.00%> (-100.00%)	⬇️
...oller/api/resources/PinotControllerAppConfigs.java	0.00% <0.00%> (-100.00%)	⬇️
... and 394 more

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[snleee]

LGTM