fix trailing comma not matched in the case of alphanumeric issue (#32945)

Fix #32428.

Patch the regex to match `,`besides `.` `"` `'` `:` and space.

modules/references/references_test.go

@@ -463,6 +463,7 @@ func TestRegExp_issueAlphanumericPattern(t *testing.T) {
 		"ABC-123:",
 		"\"ABC-123\"",
 		"'ABC-123'",
+		"ABC-123, unknown PR",
 	}
 	falseTestCases := []string{
 		"RC-08",