macOS: The command line args from macos-launch-services-cmdline are n…

…ow prefixed to any args from open --args rather than overwriting them

The purpose of the file is to provide default command line args when
launching from GUI. Since macOS nowadays also allows command line args
when launch via open, also respect them.

Fixes kovidgoyal#7135

version-0.32.2

version-0.32.1

version-0.32.0

version-0.31.0

version-0.30.1

version-0.30.0

version-0.29.2

version-0.29.1

version-0.29.0