Backoffice JS dependency updates (#14179)

* updates @babel/* to 7.21.4

* update @microsoft/signalr to 7.0.5

* update @umbraco-ui/uui to 1.2.1

* update ace editor to 1.18.0

* update all build dependencies to latest version

* update jquery to 3.6.4

* update spectrum-colorpicker2 to 2.0.10

* Add icon for "styles" alias (style select)

* update tinymce to 6.4.2

Read more here: https://www.tiny.cloud/docs/tinymce/6/6.4.1-release-notes/

Author: iOvergaard