Remove incorrect return statement

This prevented conflicts between some tokens from being recorded
properly. In the case of JavaScript, it prevented tree-sitter from
recognizing the conflict between the forward slash operator and the
regex token, allowing regexes to be merged into parse states containing
'/' incorrectly.

Refs tree-sitter/tree-sitter-javascript#71

src/compiler/build_tables/lex_table_builder.cc

@@ -310,7 +310,6 @@ class LexTableBuilderImpl : public LexTableBuilder {
             } else {
               record_conflict(accept_action.symbol, advance_symbol, MatchesLongerString);
             }
-            return;
           }
         }