chore(profiling): increase ref before stealing (#15031)

## Description

Noticed this while looking into crashes related to the memory profiler.
[See notebook
here](https://app.datadoghq.com/notebook/13359436/memory-profiler-crashes).
We are not sure whether this would be root cause of such crashes, but
still think it's 'logically' correct to increment the reference before
calling `PyTuple_SET_ITEM()`.

When you call `PyTuple_SET_ITEM(p, pos, obj);`, then the ownership of
the object `o` is transferred to the tuple.

- https://docs.python.org/3/c-api/tuple.html#c.PyTuple_SET_ITEM
- https://docs.python.org/3/c-api/intro.html#reference-count-details

> Stealing a reference means that when you pass a reference to a
function, that function assumes that it now owns that reference, and you
are not responsible for it any longer

> When you want to keep using an object although the reference to it
will be stolen, use
[Py_INCREF()](https://docs.python.org/3/c-api/refcounting.html#c.Py_INCREF)
to grab another reference before calling the reference-stealing
function.


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## Testing

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## Risks

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## Additional Notes

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Author: taegyunkim

ddtrace/profiling/collector/_memalloc_tb.c

@@ -301,14 +301,14 @@ traceback_to_tuple(traceback_t* tb)
 
         frame_t* frame = &tb->frames[nframe];
 
-        PyTuple_SET_ITEM(frame_tuple, 0, frame->filename);
         Py_INCREF(frame->filename);
+        PyTuple_SET_ITEM(frame_tuple, 0, frame->filename);
         PyTuple_SET_ITEM(frame_tuple, 1, PyLong_FromUnsignedLong(frame->lineno));
-        PyTuple_SET_ITEM(frame_tuple, 2, frame->name);
         Py_INCREF(frame->name);
+        PyTuple_SET_ITEM(frame_tuple, 2, frame->name);
         /* Class name */
-        PyTuple_SET_ITEM(frame_tuple, 3, empty_string);
         Py_INCREF(empty_string);
+        PyTuple_SET_ITEM(frame_tuple, 3, empty_string);
 
         // Try to set the class.  If we cannot (e.g., if the sofile is reloaded
         // without module initialization), then this will result in an error if