Merge pull request vitessio#6363 from planetscale/ds-dollar-sign

more dollar sign tests

Author: deepthi

go/vt/sqlparser/parse_test.go

@@ -63,6 +63,8 @@ var (
 		input: "select a from t",
 	}, {
 		input: "select $ from t",
+	}, {
+		input: "select a.b as a$b from $test$",
 	}, {
 		input:  "select 1 from t // aa\n",
 		output: "select 1 from t",