Fix #110727: VSE relative paths do not work with linked scenes

This is identical issue as #108094, but with image strips.

Use `ID_BLEND_PATH_FROM_GLOBAL` instead of
`BKE_main_blendfile_path_from_global`.

source/blender/sequencer/intern/render.cc

@@ -983,7 +983,7 @@ static ImBuf *seq_render_image_strip(const SeqRenderData *context,
   }
 
   BLI_path_join(filepath, sizeof(filepath), seq->strip->dirpath, s_elem->filename);
-  BLI_path_abs(filepath, BKE_main_blendfile_path_from_global());
+  BLI_path_abs(filepath, ID_BLEND_PATH_FROM_GLOBAL(&context->scene->id));
 
   /* Try to get a proxy image. */
   ibuf = seq_proxy_fetch(context, seq, timeline_frame);