fix mismatched delete [] in regex extension (#1941)

* fix mismatched delete []

* strdup needs to be free'd, not deleted

extensions/regex/CRegEx.cpp

@@ -56,7 +56,7 @@ void RegEx::Clear ()
 	re = nullptr;
 	mFree = true;
 	if (subject)
-		delete [] subject;
+		free(subject);
 	subject = nullptr;
 	mMatchCount = 0;
 }