[CI] Expose all the CI build variables of the parent #10869

	name: Bump global.json for dotnet/installer bumps
	on: pull_request_target

	jobs:
	bump-global-json:
	name: Bump global.json
	runs-on: ubuntu-latest
	# GITHUB_TOKEN change from read-write to read-only on 2024-02-01 requires permissions block
	# https://docs.opensource.microsoft.com/github/apps/permission-changes/
	# https://docs.github.com/en/actions/using-jobs/assigning-permissions-to-jobs
	permissions:
	contents: write
	if: contains(github.event.pull_request.title, 'Update dependencies from dotnet/installer') && github.actor == 'dotnet-maestro[bot]'
	steps:
	- name: 'Checkout repo'
	uses: actions/checkout@v4
	with:
	fetch-depth: 0
	repository: ${{ github.event.pull_request.head.repo.full_name }}
	ref: ${{ github.event.pull_request.head.sha }}

	- name: 'Update global.json'
	env:
	PR_NUMBER: ${{ github.event.number }}
	PR_TITLE: ${{ github.event.pull_request.title }}
	run: \|
	set -exo pipefail
	touch Make.config.inc # create a dummy file to avoid logic we don't need executed here
	make global.json
	if git diff --exit-code -- global.json; then
	echo "No global.json update necessary"
	exit 0
	fi
	git add -- global.json
	git config --global user.email "github-actions@xamarin.com"
	git config --global user.name "GitHub Actions"
	git checkout "$GITHUB_HEAD_REF"
	git commit -m "Re-generate global.json for PR #$PR_NUMBER: $PR_TITLE"
	git push

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