refactor git user config in scripts

scripts/upgrade-safe/git-user-config.sh

+#!/usr/bin/env bash
+
+set -euo pipefail -x
+
+git config user.name 'github-actions'
+git config user.email '41898282+github-actions[bot]@users.noreply.github.com'

scripts/upgrade-safe/merge-upstream.sh

@@ -2,8 +2,8 @@
 
 set -euo pipefail -x
 
+bash scripts/upgrade-safe/git-user-config.sh
+
 git fetch 'https://github.com/OpenZeppelin/openzeppelin-contracts.git'
-git config user.name 'github-actions'
-git config user.email '41898282+github-actions[bot]@users.noreply.github.com'
 git merge FETCH_HEAD -m 'Merge upstream openzeppelin-contracts into upstream-patched'
 git push

scripts/upgrade-safe/transpile-push.sh

@@ -3,9 +3,7 @@
 set -euo pipefail -x
 
 bash scripts/upgrade-safe/transpile.sh
-
-git config user.name 'github-actions'
-git config user.email '41898282+github-actions[bot]@users.noreply.github.com'
+bash scripts/upgrade-safe/git-user-config.sh
 
 COMMIT="$(git rev-parse --short HEAD)"