Ubuntu has dropped the `python` symlink to `python2` [1] instead of
redirecting it to `python3` like other distros are doing, which means
that if we want to build Mesa on Ubuntu we need the `python3` shebang.
[1] https://lists.ubuntu.com/archives/ubuntu-devel/2020-January/040882.html
Reported-by: Vinson Lee <vlee@freedesktop.org>
Signed-off-by: Eric Engestrom <eric@engestrom.ch>
Acked-by: Jose Fonseca <jfonseca@vmware.com>
Reviewed-by: Alyssa Rosenzweig <alyssa@collabora.com>
Reviewed-by: Dylan Baker <dylan@pnwbakers.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/3674>
6f854145d2