include: Fixed typo in SDL_CopyFile's documentation.

Fixes https://github.com/libsdl-org/sdlwiki/issues/623

include/SDL3/SDL_filesystem.h

@@ -373,7 +373,7 @@ extern SDL_DECLSPEC bool SDLCALL SDL_RenamePath(const char *oldpath, const char
  * Note that this is not an atomic operation! If something tries to read from
  * `newpath` while the copy is in progress, it will see an incomplete copy of
  * the data, and if the calling thread terminates (or the power goes out)
- * during the copy, `oldpath`'s previous contents will be gone, replaced with
+ * during the copy, `newpath`'s previous contents will be gone, replaced with
  * an incomplete copy of the data. To avoid this risk, it is recommended that
  * the app copy to a temporary file in the same directory as `newpath`, and if
  * the copy is successful, use SDL_RenamePath() to replace `newpath` with the