Sync SDL3 wiki -> header

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include/SDL3/SDL_stdinc.h

@@ -3212,7 +3212,7 @@ extern SDL_DECLSPEC char * SDLCALL SDL_strrev(char *str);
  * Convert a string to uppercase.
  *
  * **WARNING**: Regardless of system locale, this will only convert ASCII
- * values 'A' through 'Z' to uppercase.
+ * values 'a' through 'z' to uppercase.
  *
  * This function operates on a null-terminated string of bytes--even if it is
  * malformed UTF-8!--and converts ASCII characters 'a' through 'z' to their