[MM-62408] Server Code Coverage with Fully Parallel Tests (#30078)

* TestPool

* Store infra

* Store tests updates

* Bump maximum concurrent postgres connections

* More infra

* channels/jobs

* channels/app

* channels/api4

* Protect i18n from concurrent access

* Replace some use of os.Setenv

* Remove debug

* Lint fixes

* Fix more linting

* Fix test

* Remove use of Setenv in drafts tests

* Fix flaky TestWebHubCloseConnOnDBFail

* Fix merge

* [MM-62408] Add CI job to generate test coverage (#30284)

* Add CI job to generate test coverage

* Remove use of Setenv in drafts tests

* Fix flaky TestWebHubCloseConnOnDBFail

* Fix more Setenv usage

* Fix more potential flakyness

* Remove parallelism from flaky test

* Remove conflicting env var

* Fix

* Disable parallelism

* Test atomic covermode

* Disable parallelism

* Enable parallelism

* Add upload coverage step

* Fix codecov.yml

* Add codecov.yml

* Remove redundant workspace field

* Add Parallel() util methods and refactor

* Fix formatting

* More formatting fixes

* Fix reporting

server/channels/app/file_info_test.go

@@ -15,6 +15,7 @@ import (
 )
 
 func TestGetInfoForFile(t *testing.T) {
+	mainHelper.Parallel(t)
 	fakeFile := make([]byte, 1000)
 
 	pngFile, err := os.ReadFile("tests/test.png")
@@ -26,7 +27,7 @@ func TestGetInfoForFile(t *testing.T) {
 	animatedGifFile, err := os.ReadFile("tests/testgif.gif")
 	require.NoError(t, err, "Failed to load testgif.gif")
 
-	var ttc = []struct {
+	ttc := []struct {
 		testName                string
 		filename                string
 		file                    []byte