[MM-49989] Pass a context.Context to Client4 methods (#22922)

* Migrate all method in model/client4.go to accept a context.Context

* Fix th.*Client

* Fix remaining issues

* Empty commit to triger CI

* Fix test

* Add cancellation test

* Test that returned error is context.Canceled

* Fix bad merge

* Update mmctl code

---------

Co-authored-by: Mattermost Build <build@mattermost.com>

server/channels/api4/cluster_test.go

@@ -4,6 +4,7 @@
 package api4
 
 import (
+	"context"
 	"testing"
 
 	"github.com/stretchr/testify/require"
@@ -16,13 +17,13 @@ func TestGetClusterStatus(t *testing.T) {
 	defer th.TearDown()
 
 	t.Run("as system user", func(t *testing.T) {
-		_, resp, err := th.Client.GetClusterStatus()
+		_, resp, err := th.Client.GetClusterStatus(context.Background())
 		require.Error(t, err)
 		CheckForbiddenStatus(t, resp)
 	})
 
 	t.Run("as system admin", func(t *testing.T) {
-		infos, _, err := th.SystemAdminClient.GetClusterStatus()
+		infos, _, err := th.SystemAdminClient.GetClusterStatus(context.Background())
 		require.NoError(t, err)
 
 		require.NotNil(t, infos, "cluster status should not be nil")
@@ -31,7 +32,7 @@ func TestGetClusterStatus(t *testing.T) {
 	t.Run("as restricted system admin", func(t *testing.T) {
 		th.App.UpdateConfig(func(cfg *model.Config) { *cfg.ExperimentalSettings.RestrictSystemAdmin = true })
 
-		_, resp, err := th.SystemAdminClient.GetClusterStatus()
+		_, resp, err := th.SystemAdminClient.GetClusterStatus(context.Background())
 		require.Error(t, err)
 		CheckForbiddenStatus(t, resp)
 	})