Remove useless subshell from alma9 docker driver script

Since it runs `exec docker ...` as the last step, putting it inside a
subhsell is not so useful.

Author: wade-arista

contrib/alma9_rpmbuild_docker/run.sh

@@ -36,7 +36,6 @@ docker_args=(
    -i
    -t
 )
-(
-   set -x
-   exec docker run "${docker_args[@]}" "$tag" "$@"
-)
+
+set -x
+exec docker run "${docker_args[@]}" "$tag" "$@"