checker: fix mut var option unwrap with `!= none` #3059

	name: Docker CI

	on:
	push:
	paths-ignore:
	- '**.md'
	- '**.yml'
	- '!**/docker_ci.yml'
	- 'cmd/tools/**'
	- '!cmd/tools/builders/**.v'
	pull_request:
	paths-ignore:
	- '**.md'
	- '**.yml'
	- '!**/docker_ci.yml'
	- 'cmd/tools/**'
	- '!cmd/tools/builders/**.v'

	concurrency:
	group: ${{ github.workflow }}-${{ github.ref == 'refs/heads/master' && github.sha \|\| github.ref }}
	cancel-in-progress: true

	env:
	V_CI_MUSL: 1

	jobs:
	alpine-docker-musl-gcc:
	runs-on: ubuntu-20.04
	timeout-minutes: 241
	container:
	image: thevlang/vlang:alpine-build
	env:
	VFLAGS: -cc gcc
	volumes:
	- ${{github.workspace}}:/opt/vlang
	steps:
	- name: Checkout
	uses: actions/checkout@v4
	- name: Show Environment
	run: \|
	echo "PWD:"
	pwd
	echo "ENVIRONMENT:"
	env
	echo "C Compiler:"
	gcc --version
	- name: Add dependencies
	run: apk add libc6-compat
	- name: Build V
	run: CC=gcc make
	- name: All code is formatted
	run: VJOBS=1 ./v test-cleancode
	- name: Run only essential tests
	run: VTEST_JUST_ESSENTIAL=1 ./v test-self

	ubuntu-docker-musl:
	runs-on: ubuntu-20.04
	timeout-minutes: 121
	container:
	image: thevlang/vlang:ubuntu-build
	env:
	V_CI_UBUNTU_MUSL: 1
	VFLAGS: -cc musl-gcc -gc none
	volumes:
	- ${{github.workspace}}:/opt/vlang
	steps:
	- name: Checkout
	uses: actions/checkout@v4
	- name: Build V
	run: echo $VFLAGS && make -j4 && ./v -cg -o v cmd/v
	- name: Verify `v test` works
	run: \|
	echo $VFLAGS
	./v cmd/tools/test_if_v_test_system_works.v
	./cmd/tools/test_if_v_test_system_works
	- name: All code is formatted
	run: ./v test-cleancode
	- name: Test V fixed tests
	run: ./v test-self vlib

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