xdg-desktop-portal: update to 1.15.0.

[oreo639]

Testing the changes

• I tested the changes in this PR: YES

[Duncaen]

This is a pre-release

[oreo639]

It is required by xdg-desktop-portal-gnome 43 unfortunately. (It is necessary for screenshot v2 support)

[Duncaen]

Would be more appropriate to do this with the update that would require the pre-release version.

Also why did you switch to the automatically generated release tar ball instead of the one the developers upload with a known sha256 hash?

[oreo639]

Would be more appropriate to do this with the update that would require the pre-release version.

I did. That was a separate PR. #39521

Also why did you switch to the automatically generated release tar ball instead of the one the developers upload with a known sha256 hash?

The autogen dist was missing some of the test files.
Although I ended up leaving the pytest tests disabled since it couldn't find the xdg-desktop-portal executable.

It can be switched back, sorry about that.