Remove insights (#23952)

* removed server side

* Updated store layer

* unused import

* Updated autogenerated code template

* Updated tests

* lint fix

* unused translations

* webapp side

* Updated i18n

* lint fix:

* type fix

* Updated snapshots

* Removed insights from API specs

* updated e2e

* Updated e2e tests

* Updated e2e tests

* Removed insights tests

* Removed Insights as possible channel to load in sidebar from test

* Removed more insights tests

* More e2e fixed

* More cleanup

* Lint

* More cleanup in client4 and boards api

* More cleanup

* Fixes

* lint fix

---------

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

server/channels/api4/preference_test.go

@@ -50,8 +50,8 @@ func TestGetPreferences(t *testing.T) {
 	prefs, _, err := client.GetPreferences(context.Background(), user1.Id)
 	require.NoError(t, err)
 
-	// 6 because we have 3 initial preferences insights, tutorial_step and recommended_next_steps added when creating a new user
-	require.Equal(t, len(prefs), 6, "received the wrong number of preferences")
+	// 5 because we have 2 initial preferences tutorial_step and recommended_next_steps added when creating a new user
+	require.Equal(t, len(prefs), 5, "received the wrong number of preferences")
 
 	for _, preference := range prefs {
 		require.Equal(t, preference.UserId, th.BasicUser.Id, "user id does not match")