MM-25641: Check if member was deleted in HasPermissionToTeam (#14737)

This PR adds a check to verify if a team member got deleted in HasPermissionToTeam,
and accordingly returns false.

app/authorization_test.go

@@ -6,6 +6,7 @@ package app
 import (
 	"testing"
 
+	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
 
 	"github.com/mattermost/mattermost-server/v5/model"
@@ -41,3 +42,14 @@ func TestChannelRolesGrantPermission(t *testing.T) {
 		require.Equal(t, testData.shouldHavePermission, th.App.RolesGrantPermission([]string{testData.channelRole.Name}, testData.permission.Id), "row: %+v\n", testData.truthTableRow)
 	})
 }
+
+func TestHasPermissionToTeam(t *testing.T) {
+	th := Setup(t).InitBasic()
+	defer th.TearDown()
+
+	assert.True(t, th.App.HasPermissionToTeam(th.BasicUser.Id, th.BasicTeam.Id, model.PERMISSION_LIST_TEAM_CHANNELS))
+
+	th.RemoveUserFromTeam(th.BasicUser, th.BasicTeam)
+
+	assert.False(t, th.App.HasPermissionToTeam(th.BasicUser.Id, th.BasicTeam.Id, model.PERMISSION_LIST_TEAM_CHANNELS))
+}