CI/macOS: Update to macOS 13

[guihkx]

This is mainly done because Homebrew has recently dropped support for macOS 12, which causes a massive slowdown in CI when installing Qt 6, because it has to be built from source.

Closes #699

[guihkx]

Apparently, GitHub's macOS 13 runner can cause some spurious errors when running create-dmg:

It seems to be a very common error, too: actions/runner-images#7522

The Qt 6 build passed the first attempt, but the Qt 5 one needed 5(!) rebuilds to finally pass... 😢

---

Anyway, just to be sure, I've tested the resulting Qt 5 and Qt 6 build artifacts on macOS 11 Big Sur, and they still work:

Qt 5:

Screenshot

Qt 6:

Screenshot

[nuttyartist]

Damn, @guihkx thanks so much for this work!

[nuttyartist]

Did we solve the hdiutil failures?

[guihkx]

In a way, yes.

Now we keep invoking it until it works:

notes/.github/workflows/macos.yml

Lines 151 to 176 in 57542f6

	# FIXME: Undo this overengineered crap once the following issue gets figured out:
	# https://github.com/actions/runner-images/issues/7522
	max_tries=10
	i=0
	until create-dmg \
	--no-internet-enable \
	--format ULFO \
	--background ../packaging/macos/dmg-background.png \
	--hide-extension 'Notes Better.app' \
	--icon 'Notes Better.app' 180 170 \
	--icon-size 160 \
	--text-size 12 \
	--volname Notes \
	--volicon ../src/images/notes_icon.icns \
	--window-size 660 400 \
	--app-drop-link 480 170 \
	'${{ steps.vars.outputs.file_name }}' \
	'Notes Better.app'
	do
	if [ $i -eq $max_tries ]
	then
	echo 'Error: create-dmg did not succeed even after 10 tries.'
	exit 1
	fi
	i=$((i+1))
	done

[nuttyartist]

I forgot, did using root didn't work?

[guihkx]

Nope.

I tried that on #712, and it failed right after the PR got merged: https://github.com/nuttyartist/notes/actions/runs/11423877142/job/31783553788#step:13

[nuttyartist]

Alrighty, thanks for all the info!