[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/api4/websocket_test.go

@@ -21,6 +21,7 @@ import (
 )
 
 func TestWebSocketTrailingSlash(t *testing.T) {
+	mainHelper.Parallel(t)
 	th := Setup(t)
 	defer th.TearDown()
 
@@ -30,6 +31,7 @@ func TestWebSocketTrailingSlash(t *testing.T) {
 }
 
 func TestWebSocketEvent(t *testing.T) {
+	mainHelper.Parallel(t)
 	th := Setup(t).InitBasic()
 	defer th.TearDown()
 
@@ -95,6 +97,7 @@ func TestWebSocketEvent(t *testing.T) {
 }
 
 func TestCreateDirectChannelWithSocket(t *testing.T) {
+	mainHelper.Parallel(t)
 	th := Setup(t).InitBasic()
 	defer th.TearDown()
 
@@ -150,6 +153,7 @@ func TestCreateDirectChannelWithSocket(t *testing.T) {
 }
 
 func TestWebsocketOriginSecurity(t *testing.T) {
+	mainHelper.Parallel(t)
 	th := Setup(t)
 	defer th.TearDown()
 
@@ -200,6 +204,7 @@ func TestWebsocketOriginSecurity(t *testing.T) {
 }
 
 func TestWebSocketReconnectRace(t *testing.T) {
+	mainHelper.Parallel(t)
 	th := Setup(t).InitBasic()
 	defer th.TearDown()
 
@@ -234,6 +239,7 @@ func TestWebSocketReconnectRace(t *testing.T) {
 }
 
 func TestWebSocketSendBinary(t *testing.T) {
+	mainHelper.Parallel(t)
 	th := Setup(t).InitBasic()
 	defer th.TearDown()
 
@@ -273,6 +279,7 @@ func TestWebSocketSendBinary(t *testing.T) {
 }
 
 func TestWebSocketStatuses(t *testing.T) {
+	mainHelper.Parallel(t)
 	th := Setup(t).InitBasic()
 	defer th.TearDown()
 
@@ -412,6 +419,7 @@ func TestWebSocketStatuses(t *testing.T) {
 }
 
 func TestWebSocketPresence(t *testing.T) {
+	mainHelper.Parallel(t)
 	th := Setup(t).InitBasic()
 	defer th.TearDown()
 
@@ -442,6 +450,7 @@ func TestWebSocketPresence(t *testing.T) {
 }
 
 func TestWebSocketUpgrade(t *testing.T) {
+	mainHelper.Parallel(t)
 	th := Setup(t)
 	defer th.TearDown()