Convert TrackerUserUidTest into a Kernel test. Deprecate TrackerTestBase

This patch decreases the locally test run from 12.6 to 2.8 seconds.

Problem/Motivation

TrackerUserUidTest makes no HTTP requests but is a functional test

Proposed resolution

• Convert TrackerUserUidTest into a Kernel test.
• TrackerTestBase has lost the use cases from Drupal core. More, the integration with Views should be tested with Kernel tests, as it don't involve HTTP requests.

Remaining tasks

None.

User interface changes

None.

API changes

TrackerTestBase is deprecated.

Data model changes

None.

Release notes snippet

N/A