Fix some syntaxes overwriting variable list indices and add new helper method for changing expressions. #6542

	name: JUnit (MC 1.17-1.20.4)

	on:
	push:
	branches:
	- master
	- 'dev/**'
	pull_request:

	jobs:
	build:
	if: "! contains(toJSON(github.event.commits.*.message), '[ci skip]')"
	runs-on: ubuntu-latest
	steps:
	- uses: actions/checkout@v4
	with:
	submodules: recursive
	- name: validate gradle wrapper
	uses: gradle/wrapper-validation-action@v2
	- name: Set up JDK 21
	uses: actions/setup-java@v4
	with:
	java-version: '21'
	distribution: 'adopt'
	cache: gradle
	- name: Grant execute permission for gradlew
	run: chmod +x gradlew
	- name: Build Skript and run JUnit
	run: ./gradlew clean JUnitJava17

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