MACOS: Migrate to Sparkle 2 API for updates #175

Job	Run time
Xcode (macosx, -scheme ScummVM-macOS, --disable-nasm --enable-faad --enable-gif --enable-mikmod -...	24m 42s
Windows (win32, x86-windows, x86, --enable-discord --enable-faad --enable-gif --enable-mikmod --e...	55m 58s
Xcode (ios7, -scheme ScummVM-iOS CODE_SIGN_IDENTITY="" CODE_SIGNING_ALLOWED=NO, --use-xcframework...	32m 51s
Ubuntu (ubuntu-latest, sdl2-config, ccache g++, liba52-dev libcurl4-openssl-dev libfaad-dev libfl...	25m 19s
Windows (x64, x64, x64-windows, --enable-discord --enable-faad --enable-gif --enable-mikmod --ena...	44m 30s
Ubuntu (ubuntu-20.04, sdl-config, ccache g++-4.8, g++-4.8 liba52-dev libcurl4-openssl-dev libfaad...	20m 24s
Windows (arm64, arm64, arm64-windows, --enable-discord --enable-faad --enable-gif --enable-mikmod...	54m 13s
	4h 17m 57s

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