[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/usage_test.go

@@ -4,6 +4,7 @@
 package api4
 
 import (
+	"context"
 	"net/http"
 	"testing"
 
@@ -18,9 +19,9 @@ func TestGetPostsUsage(t *testing.T) {
 		th := Setup(t)
 		defer th.TearDown()
 
-		th.Client.Logout()
+		th.Client.Logout(context.Background())
 
-		usage, r, err := th.Client.GetPostsUsage()
+		usage, r, err := th.Client.GetPostsUsage(context.Background())
 		assert.Error(t, err)
 		assert.Nil(t, usage)
 		assert.Equal(t, http.StatusUnauthorized, r.StatusCode)
@@ -43,7 +44,7 @@ func TestGetPostsUsage(t *testing.T) {
 		require.LessOrEqual(t, usersOnly, int64(20))
 		require.GreaterOrEqual(t, total, usersOnly)
 
-		usage, r, err := th.Client.GetPostsUsage()
+		usage, r, err := th.Client.GetPostsUsage(context.Background())
 		assert.NoError(t, err)
 		assert.Equal(t, http.StatusOK, r.StatusCode)
 		assert.NotNil(t, usage)
@@ -56,9 +57,9 @@ func TestGetStorageUsage(t *testing.T) {
 		th := Setup(t)
 		defer th.TearDown()
 
-		th.Client.Logout()
+		th.Client.Logout(context.Background())
 
-		usage, r, err := th.Client.GetStorageUsage()
+		usage, r, err := th.Client.GetStorageUsage(context.Background())
 		assert.Error(t, err)
 		assert.Nil(t, usage)
 		assert.Equal(t, http.StatusUnauthorized, r.StatusCode)
@@ -70,9 +71,9 @@ func TestGetTeamsUsage(t *testing.T) {
 		th := Setup(t)
 		defer th.TearDown()
 
-		th.Client.Logout()
+		th.Client.Logout(context.Background())
 
-		usage, r, err := th.Client.GetTeamsUsage()
+		usage, r, err := th.Client.GetTeamsUsage(context.Background())
 		assert.Error(t, err)
 		assert.Nil(t, usage)
 		assert.Equal(t, http.StatusUnauthorized, r.StatusCode)
@@ -85,7 +86,7 @@ func TestGetTeamsUsage(t *testing.T) {
 		th.CreateTeam()
 		th.CreateTeam()
 
-		usage, r, err := th.Client.GetTeamsUsage()
+		usage, r, err := th.Client.GetTeamsUsage(context.Background())
 		assert.NoError(t, err)
 		assert.Equal(t, http.StatusOK, r.StatusCode)
 		assert.NotNil(t, usage)