[macOS] Print full source paths in the trace.

[bruvzg]

Adds full (or relative) paths to the trace, for consistency with other platforms.

Before:

[17] SceneTree::initialize() (in godot.macos.editor.dev.arm64) (scene_tree.cpp:572)
[18] OS_MacOS::run() (in godot.macos.editor.dev.arm64) (os_macos.mm:800)
[19] main (in godot.macos.editor.dev.arm64) (godot_main_macos.mm:84)

After, with debug_paths_relative=false:

[17] SceneTree::initialize() (in godot.macos.editor.dev.arm64) (/Volumes/Backup/Projects/godot/scene/main/scene_tree.cpp:572)
[18] OS_MacOS::run() (in godot.macos.editor.dev.arm64) (/Volumes/Backup/Projects/godot/platform/macos/os_macos.mm:800)
[19] main (in godot.macos.editor.dev.arm64) (/Volumes/Backup/Projects/godot/platform/macos/godot_main_macos.mm:84)

After, with debug_paths_relative=true:

[17] SceneTree::initialize() (in godot.macos.editor.dev.arm64) (./scene/main/scene_tree.cpp:572)
[18] OS_MacOS::run() (in godot.macos.editor.dev.arm64) (./platform/macos/os_macos.mm:800)
[19] main (in godot.macos.editor.dev.arm64) (./platform/macos/godot_main_macos.mm:84)

[akien-mga]

Thanks!