Downgrade antlr to 4.8 to match Nessie

[omarsmak]

Downgrade antlr version in CEL library to match what we have in Nessie (4.8). In Nessie build logs I saw some warnings and errors related to the version mismatch, e.g:

2021-10-20T13:46:37.3349023Z [ERROR] ANTLR Tool version 4.9.2 used for code generation does not match the current runtime version 4.8
2021-10-20T13:46:37.3352032Z [ERROR] ANTLR Runtime version 4.9.2 used for parser compilation does not match the current runtime version 4.8
2021-10-20T13:46:37.3749587Z [ERROR] ANTLR Tool version 
2021-10-20T13:46:37.3754222Z [ERROR] 4.9.2
2021-10-20T13:46:37.3759485Z [ERROR]  used for code generation does not match the current runtime version 4.8
2021-10-20T13:46:37.3769785Z [ERROR] ANTLR Runtime version 4.9.2 used for parser compilation does not match the current runtime version 4.8

And it seems we can't upgrade antlr in Nessie since it needs to match antlr version in Spark as it is using 4.8 as well per this PR

cc @snazy

[snazy]

I'm okay to downgrade it.
Feel free to merge #49 if CI looks good and rebase this one.

[omarsmak]

I'm okay to downgrade it. Feel free to merge #49 if CI looks good and rebase this one.

It seems I have no enough permissions on this repo to merge

[laurentgo]

Is Antlr a requirement from the CEL format? Could it be possible to switch to a model where we don't depend on some specific runtime for code generation (which happens at compile time?)

[laurentgo]

(Sorry, closed by mistake, reopening)

[codecov]

Codecov Report

Merging #48 (9c16819) into main (47041bd) will not change coverage.
The diff coverage is n/a.

@@            Coverage Diff            @@
##               main      #48   +/-   ##
=========================================
  Coverage     79.92%   79.92%           
  Complexity     1753     1753           
=========================================
  Files            97       97           
  Lines          7611     7611           
  Branches       1117     1117           
=========================================
  Hits           6083     6083           
  Misses         1021     1021           
  Partials        507      507           

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[snazy]

Is Antlr a requirement from the CEL format? Could it be possible to switch to a model where we don't depend on some specific runtime for code generation (which happens at compile time?)

@laurentgo it's tricky. all the CEL syntax parsing is based on the existing antlr grammar. I think cel-java should just shade the antlr classes (#52).