Remove dev feature guard from ESQL antlr files

Author: jbaiera

x-pack/plugin/esql/src/main/antlr/EsqlBaseParser.g4

@@ -100,7 +100,7 @@ indexPatternAndMetadataFields:
 
 indexPattern
     : (clusterString COLON)? indexString
-    | {this.isDevVersion()}? indexString (CAST_OP selectorString)?
+    | indexString (CAST_OP selectorString)?
     ;
 
 clusterString

x-pack/plugin/esql/src/main/antlr/lexer/From.g4

@@ -18,7 +18,7 @@ FROM_PIPE : PIPE -> type(PIPE), popMode;
 FROM_OPENING_BRACKET : OPENING_BRACKET -> type(OPENING_BRACKET);
 FROM_CLOSING_BRACKET : CLOSING_BRACKET -> type(CLOSING_BRACKET);
 FROM_COLON : COLON -> type(COLON);
-FROM_SELECTOR : {this.isDevVersion()}? CAST_OP -> type(CAST_OP);
+FROM_SELECTOR : CAST_OP -> type(CAST_OP);
 FROM_COMMA : COMMA -> type(COMMA);
 FROM_ASSIGN : ASSIGN -> type(ASSIGN);
 METADATA : 'metadata';