refactor(sterni/git-only-push): use --reverse over tac(1)

Change-Id: I29375563eb1395f23175446dbbd9a760ddaaffad
Reviewed-on: https://cl.tvl.fyi/c/depot/+/13153
Autosubmit: sterni <sternenseemann@systemli.org>
Tested-by: BuildkiteCI
Reviewed-by: sterni <sternenseemann@systemli.org>

users/sterni/git-only-push/git-only-push.sh

@@ -107,7 +107,7 @@ fi
 
 for arg in "$@"; do
   # Resolve ranges, get them into chronological order
-  revs="$(git -C "$repo" rev-list --no-walk "$arg" | tac)"
+  revs="$(git -C "$repo" rev-list --reverse --no-walk "$arg")"
 
   for rev in $revs; do
     if $dry; then