Currently when the user doesn't specify a branch to the run command, for
apps it will use the current branch and for runtimes it just tries to
use "master" and fails if that doesn't work. Since runtimes don't have
current branches, it would be nice if we could determine the right one
to use rather than just erroring out. So this commit changes the
implementation so that it looks at each installed runtime and if only
one matches it is used. If there's more than one match the user is
prompted to choose. This is the first interactivity added to the run
command but I don't think that's an issue; any time it's run in a
non-interactive shell it will error out upon encountering ambiguity.
Also, add a couple unit tests for the success path and error paths.
Fixes https://github.com/flatpak/flatpak/issues/2780Closes: #2788
Approved by: matthiasclasen
Matthew Leeds
0b20f3d48f