anbox-cloud-tests snap fails due to confinement

[Samuel Allan]

The anbox-cloud-tests snap has strict confinement with the home interface. This interface doesn't allow access to hidden (dot) files in the home directory, but anbox-cloud-tests tries to create dotfiles in the home directory, which crashes the tests:

  benchmark failed
  Expected
      <*fs.PathError | 0xc000322450>: {
          Op: "mkdir",
          Path: "/home/ubuntu/.benchmark426547808",
          Err: 0xd,
      }
  to be nil

Either the snap must be modified to allow creation of these directories, or anbox-cloud-tests should be configured/modified to not create files here (through the snap config and/or modifications to the codebase).