Migrate to stateless app.App (#17542)

* add request context

* move initialialization to server

* use app interface instead of global app functions

* remove app context from webconn

* cleanup

* remove duplicated services

* move context to separate package

* remove finalize init method and move content to NewServer function

* restart workers and schedulers after adding license for tests

* reflect review comments

Co-authored-by: Mattermod <mattermod@users.noreply.github.com>

app/slashcommands/command_code_test.go

@@ -21,7 +21,7 @@ func TestCodeProviderDoCommand(t *testing.T) {
 		"foo\nbar":   "    foo\n    bar",
 		"foo\nbar\n": "    foo\n    bar\n    ",
 	} {
-		actual := cp.DoCommand(nil, args, msg).Text
+		actual := cp.DoCommand(nil, nil, args, msg).Text
 		if actual != expected {
 			t.Errorf("expected `%v`, got `%v`", expected, actual)
 		}