fix(ci): add git clean before pull

Author: mpsq

scripts/build-artifacts.bash

@@ -15,7 +15,7 @@ MAKEFLAGS="-j$(nproc)"
 export MAKEFLAGS
 
 pushd emacs || exit
-su-exec "$USR" make distclean
+su-exec "$USR" make extraclean
 popd || exit
 su-exec "$USR" makepkg
 

scripts/pull.bash

@@ -4,6 +4,7 @@ set -euxo pipefail
 
 if [[ -d "emacs" ]]; then
   cd emacs
+  git clean -fX
   git checkout .
   git pull --rebase origin "$UPSTREAM_BRANCH"
 else