Add lcov exclusion markers to jsonpath scanner

This was done for all scanners in
42116736 but not added to the new one.

src/backend/utils/adt/jsonpath_scan.l

@@ -43,6 +43,8 @@ fprintf_to_ereport(const char *fmt, const char *msg)
 	ereport(ERROR, (errmsg_internal("%s", msg)));
 }
 
+/* LCOV_EXCL_START */
+
 %}
 
 %option 8bit
@@ -271,6 +273,8 @@ hex_fail	\\x{hex_dig}{0,1}
 
 %%
 
+/* LCOV_EXCL_STOP */
+
 void
 jsonpath_yyerror(JsonPathParseResult **result, const char *message)
 {