tools/lrama: add missing newline at end of yacc.c template

posix requires text files to end with a newline character.
pre-commit hook detected the missing newline and this fixes it.

Co-authored-by: Claude <noreply@anthropic.com>

tools/lrama/template/bison/yacc.c

@@ -2065,3 +2065,4 @@ yyreturnlab:
 #line <%= output.aux.epilogue_first_lineno - 1 %> "<%= output.grammar_file_path %>"
 <%= output.aux.epilogue -%>
 <%- end -%>
+