feat: migrate to antlr4ng (#267)

* feat: replace antlr4ts with antlr4ng

* feat: switch caseInsensitive option on

* feat: recompile all g4 file

* feat:  update parser to fit antlr4ng

* test: update test to fit antlr4ng

src/grammar/spark/SparkSqlLexer.g4

@@ -25,6 +25,10 @@
 
 lexer grammar SparkSqlLexer;
 
+options {
+    caseInsensitive= true;
+}
+
 @members {
   /**
    * When true, parser should throw ParseException for unclosed bracketed comment.
@@ -469,7 +473,7 @@ fragment EXPONENT: 'E' [+-]? DIGIT+;
 
 fragment DIGIT: [0-9];
 
-fragment LETTER: [A-Za-z];
+fragment LETTER: [A-Z];
 
 SIMPLE_COMMENT: '--' ('\\\n' | ~[\r\n])* '\r'? '\n'? -> channel(HIDDEN);
 

src/grammar/spark/SparkSqlParser.g4

@@ -26,6 +26,7 @@ parser grammar SparkSqlParser;
 
 options {
     tokenVocab=SparkSqlLexer;
+    caseInsensitive= true;
 }
 
 program