* api4: fix TestGetUsersNotInTeam assertions
This test was relying on data from a previous test run. With the data cleared before each test, the assertions much match reality.
* *testlib: always InitSystemAdmin
Some tests implicitly relied on the basic user having system
administrator privileges because it was the first user created as such.
Eliminate `InitSystemAdmin` and explicitly create the system admin user
instead to avoid this ambiguity going forward.
* *testlib: drop all tables before each test
* api4: split up TestChannelDelete to avoid duplicate InitBasic
* api4: teardown in TestResetPassword, for when this test comes back
* invalidate cache on DropAllTables
This is necessary since the test store persists across tests.
* disable parallel tests
While tests within a package must be explicitly parallelized using `t.Parallel()`, tests across packages are run in parallel by default. This causes problems given that the tests all currently share the same database instance.
Unfortunately, this also means that running the tests is much slower, but we can return to this later.
* Moving goroutine pool
* Auto refactor
* Moving plugins.
* Auto refactor
* Moving fields to server
* Auto refactor
* Removing siteurl duplication.
* Moving reset of app fields
* Auto refactor
* Formatting
* Moving niling of Server to after last use
* Fixing unit tests.
* MM-9728: Online migration for advanced permissions phase 2
* Add unit tests for new store functions.
* Move migration specific code to own file.
* Add migration state function test.
* Style fixes.
* Add i18n strings.
* Fix mocks.
* Add TestMain to migrations package tests.
* Fix typo.
* Fix review comments.
* Fix up the "Check if migration is done" check to actually work.
