[1.21.1] Allow mods to add custom FeatureFlags #3805

	# File generated by the GradleUtils `setupGitHubActionsWorkflows` task, avoid modifying it directly
	# The template can be found at https://github.com/neoforged/GradleUtils/blob/44d9e09cfa2c6032b84ac40495ea5ab7d64fe521/src/actionsTemplate/resources/.github/workflows/build-prs.yml

	name: Build PRs

	on:
	pull_request:
	types:
	- synchronize
	- opened
	- ready_for_review
	- reopened
	push:
	branches:
	- 'feature/**'
	workflow_dispatch:

	jobs:
	build:
	runs-on: ubuntu-latest
	steps:
	- name: Checkout repository
	uses: actions/checkout@v4
	with:
	fetch-depth: 1000
	fetch-tags: true

	# GradleUtils will append the branch name to the version,
	# but for that we need a properly checked out branch
	- name: Create branch for commit
	run:
	git switch -C pr-${{ github.event.pull_request.number }}-${{ github.event.pull_request.head.ref }}

	- name: Setup JDK 21
	uses: neoforged/actions/setup-java@main
	with:
	java-version: 21

	- name: Setup Gradle
	uses: gradle/actions/setup-gradle@v4
	with:
	cache-read-only: false

	- name: Setup with Gradle
	run: ./gradlew :neoforge:setup -PvalidateAccessTransformers

	- name: Build with Gradle
	run: ./gradlew assemble checkFormatting

	- name: Run JCC
	run: ./gradlew checkJarCompatibility

	- name: Upload JCC
	uses: neoforged/action-jar-compatibility/upload@v1

	- name: Publish artifacts
	uses: neoforged/action-pr-publishing/upload@v1

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