gh: Stop using macos11 runners

This removes the macos11 usage from github actions, and starts using macos14
macos11 runners are deprecated or removed from github actions:
https://github.blog/changelog/2024-05-20-actions-upcoming-changes-to-github-hosted-macos-runners/
# Veuillez saisir le message de validation pour vos modifications. Les lignes
# commençant par '#' seront ignorées, et un message vide abandonne la validation.
#
# Sur la branche nomacos11

# Modifications qui seront validées :
#	modifié :         .github/workflows/compile.yml
#
# Fichiers non suivis:
#	.goreleaser.yaml
#	0001-Add-script-to-start-EFI-image.patch
#	0002-misc-improvements-to-scripts.patch
#	0003-setRawMode-work.patch
#	0004-test-with-qemu.patch
#	0005-debug-hacks.patch
#	cmd/vfkit/main.go.orig
#	cmdline.test
#	diff
#	go.mod.orig
#	go.mod.rej
#	hacks.diff
#	patch
#	pkg/config/json.go~
#	pkg/ignition/
#	rest.md
#	run-sample-vm.sh
#	start-vm.sh
#	stdout/
#	vfkit
#	vfkit-amd64
#	vfkit-arm64
#	vfkit-macos12
#

.github/workflows/compile.yml

@@ -23,9 +23,9 @@ jobs:
  fail-fast: false
  matrix:
  os:
- - macOS-11
  - macOS-12
  - macOS-13
+ - macOS-14
  steps:
  - name: Check out repository code
  uses: actions/checkout@v4
@@ -45,12 +45,11 @@ jobs:
  - name: Build
  run: make
  - name: Test
- if: matrix.os != 'macOS-11'
  run: make test
  - name: vet
  run: go vet ./...
  - name: Upload vfkit artifact
- if: matrix.os == 'macOS-13'
+ if: matrix.os == 'macOS-14'
  uses: actions/upload-artifact@v4
  with:
  name: Unsigned vfkit Universal Binary