[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_helper_test.go

@@ -13,6 +13,7 @@ import (
 )
 
 func TestFilterInaccessibleFiles(t *testing.T) {
+	mainHelper.Parallel(t)
 	th := Setup(t)
 	th.App.Srv().SetLicense(model.NewTestLicense("cloud"))
 	err := th.App.Srv().Store().System().Save(&model.System{
@@ -23,7 +24,7 @@ func TestFilterInaccessibleFiles(t *testing.T) {
 
 	defer th.TearDown()
 
-	var getFileWithCreateAt = func(at int64) *model.FileInfo {
+	getFileWithCreateAt := func(at int64) *model.FileInfo {
 		return &model.FileInfo{CreateAt: at}
 	}
 
@@ -116,6 +117,7 @@ func TestFilterInaccessibleFiles(t *testing.T) {
 }
 
 func TestGetFilteredAccessibleFiles(t *testing.T) {
+	mainHelper.Parallel(t)
 	th := Setup(t)
 	th.App.Srv().SetLicense(model.NewTestLicense("cloud"))
 	err := th.App.Srv().Store().System().Save(&model.System{
@@ -126,7 +128,7 @@ func TestGetFilteredAccessibleFiles(t *testing.T) {
 
 	defer th.TearDown()
 
-	var getFileWithCreateAt = func(at int64) *model.FileInfo {
+	getFileWithCreateAt := func(at int64) *model.FileInfo {
 		return &model.FileInfo{CreateAt: at}
 	}
 
@@ -158,6 +160,7 @@ func TestGetFilteredAccessibleFiles(t *testing.T) {
 }
 
 func TestIsInaccessibleFile(t *testing.T) {
+	mainHelper.Parallel(t)
 	th := Setup(t)
 	th.App.Srv().SetLicense(model.NewTestLicense("cloud"))
 	err := th.App.Srv().Store().System().Save(&model.System{
@@ -180,6 +183,7 @@ func TestIsInaccessibleFile(t *testing.T) {
 }
 
 func TestRemoveInaccessibleContentFromFilesSlice(t *testing.T) {
+	mainHelper.Parallel(t)
 	th := Setup(t)
 	th.App.Srv().SetLicense(model.NewTestLicense("cloud"))
 	err := th.App.Srv().Store().System().Save(&model.System{
@@ -190,7 +194,7 @@ func TestRemoveInaccessibleContentFromFilesSlice(t *testing.T) {
 
 	defer th.TearDown()
 
-	var getFileWithCreateAt = func(at int64) *model.FileInfo {
+	getFileWithCreateAt := func(at int64) *model.FileInfo {
 		return &model.FileInfo{CreateAt: at}
 	}