Squad

This 1.54.2 release uses a refactored implementation of
squad-linaro-plugins/tradefed, consuming much less memory
when computing CTS/VTS results

This 1.54.1 release improves performance of fetch tasks
by reducing the number of queries when computing tests stats.

The release also fixes a bug when fetching a job in TuxSuite
that has unknown status.

This 1.54 release bring a handful of bugfixes and improvements:

* Bug fixes
* handle LAVA HTTP/500 responses from the api
* fix several bug in the metric page and improve overall performance
* fix a race-condition bug when processing multiple result submissions

* New features
* allow filtering builds by id and testjobs by backends

Complete list of changes going in:

* api: rest: add allow filtering testjobs by backend
* api: rest: allow filtering builds by id
* ci: lava: catch submission errors on 500 errors
* ci: tuxsuite: handle failed jobs
* core: BuildSummary: add uniqueness constraint
* core: queries: improve overall query performance
* core: queries: remove extra order_by
* frontend: chart.js: avoid drawing charts on empty environments
* frontend: queries: improve query performance
* frontend: templatetags: avoid having 'None' rendered
* frontend: views: avoid None in threshold metric data

This 1.53.2 release fixes a bug in the TuxSuite backend
when fetching tests with failed builds. The release also
fixes the number of tests used when calculating the confidence
score for a given test.

This 1.53.1 release includes a missing "metadata" field
in tests api REST endpoint.

This 1.53 release drops Django 2.2 support in SQUAD and
add support to 3.2 and 4.0.