Bundle mir_flutter_app into mir-test-tools snap

[hbatagelo]

Adds mir-flutter-app built from source into the snap. When the client is executed, it is kept alive for 120 seconds. This is enough for mir-ci to run the automated integration tests using the Robot framework.

NB: The reference application needs support for the mir_shell extension. This is currently not available in the mir_demo_server from the release ppa.

[mattkae]

Hmm CI is broken, although it doesn't seem to be your fault, right?

[AlanGriffiths]

Hmm CI is broken, although it doesn't seem to be your fault, right?

Yeah, the arm{hf,64} builds are failing everywhere I look

[mattkae]

Hmm CI is broken, although it doesn't seem to be your fault, right?

Yeah, the arm{hf,64} builds are failing everywhere I look

Should that guard this PR from going in? Looks unrelated...

[AlanGriffiths]

Should that guard this PR from going in? Looks unrelated...

In principle, no.

But, I think this is an "improvement" to snapcraft remote-build that prevents us computing the version and grade for the snap. Give me a couple of hours to explore the options for fixing before landing.

[AlanGriffiths]

The underlying problem is that snapcraft remote-build is broken. That is in turn breaking our GHA for arm{hf,64}

[mattkae]

Working for me :)