Fix T51692: issue when passing temporary directory.

Since BAM wants to handle all paths as bytes, care should be taken to
always encode.

bam/blend/blendfile_pack.py

@@ -661,7 +661,7 @@ def main():
             args.path_src.encode('utf8'),
             args.path_dst.encode('utf8'),
             mode=args.mode,
-            base_dir_dst_temp=args.temp_path,
+            base_dir_dst_temp=args.temp_path.encode('utf8'),
             filename_filter=exclusion_filter(args.exclude),
             ):
         report(msg)