Update Installer tests to not use Bartik and Seven

Problem/Motivation

There are several tests that have references to Bartik and Seven:

         1 core/tests/Drupal/FunctionalTests/Installer/DistributionProfileExistingSettingsTest.php
   1 core/tests/Drupal/FunctionalTests/Installer/DistributionProfileTest.php
   1 core/tests/Drupal/FunctionalTests/Installer/DistributionProfileTranslationQueryTest.php
   1 core/tests/Drupal/FunctionalTests/Installer/DistributionProfileTranslationTest.php
   1 core/tests/Drupal/FunctionalTests/Installer/InstallerTest.php
   2 core/tests/Drupal/FunctionalTests/Installer/MultipleDistributionsProfileTest.php
   1 core/tests/Drupal/FunctionalTests/Installer/StandardInstallerTest.php

These tests should be updated to either use Olivero, Claro, or System module's test_theme so we can deprecate Bartik #3249109: Deprecate Bartik in core once Olivero is the default theme and Seven #3084814: Deprecate Seven theme as mentioned at #3278124: Convert various tests that use bartik/seven to olivero/claro.

Steps to reproduce

git grep -E '(bartik)|(seven)' -- 'core/tests/Drupal/FunctionalTests/Installer' | awk -F: '{print $1}' | sort | uniq -c should return no results when this work is complete.

Remaining tasks

Update the tests.

User interface changes

None.

API changes

None.

Data model changes

None.

Release notes snippet

I don't think we need release notes or a change record.