buffer: Remove trailing space

Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/5355>

subprojects/gstreamer/gst/gstbuffer.c

@@ -35,7 +35,7 @@
  * The following example creates a buffer that can hold a given video frame
  * with a given width, height and bits per plane.
  *
- * ``` C 
+ * ``` C
  *   GstBuffer *buffer;
  *   GstMemory *memory;
  *   gint size, width, height, bpp;