Fix memory leak when closing Title Sequence handle.

The handle is now invalid after calling TitleSequenceCloseParkHandle().

src/openrct2/title/TitleSequence.cpp

@@ -166,6 +166,7 @@ extern "C"
         {
             Memory::Free(handle->HintPath);
             delete ((IStream *)handle->Stream);
+            Memory::Free(handle);
         }
     }
 

src/openrct2/title/TitleSequence.h

@@ -88,6 +88,11 @@ extern "C"
     void FreeTitleSequence(TitleSequence * seq);
 
     TitleSequenceParkHandle * TitleSequenceGetParkHandle(TitleSequence * seq, size_t index);
+
+    /**
+     * Close a title sequence park handle.
+     * The pointer to the handle is invalid after calling this function.
+     */
     void TitleSequenceCloseParkHandle(TitleSequenceParkHandle * handle);
     bool TileSequenceSave(TitleSequence * seq);
     bool TileSequenceAddPark(TitleSequence * seq, const utf8 * path, const utf8 * name);