GitLab

* Add tests for prefixed attributes.
* Move prefix removal to WikiModel and add duplicate attribute handling
  to ensure that, e.g., translated href attributes are correctly handled
  in WikiModel.

* Change HTML renderers to only print allowed attributes and elements.
* Add prefix to forbidden attributes to preserve them in XWiki syntax.
* Adapt tests to expect that invalid attributes get a prefix.

* Introduce the operations to set several macro categories
* Introduce xwiki-rendering-legacy-transformation-macro legacy module
* Move AbstractMacroDescriptor.setDefaultCategory to xwiki-rendering-legacy-transformation-macro
* Some deprecated methods are temporarily kept until their use is removed from xwiki-platform

XRENDERING-668: Attributes starting with data-xwiki- aren't preserved during XHTML parsing

* Only remove attributes when the tag is a metadata tag.
* Add tests.

Currently translated at 100.0% (3 of 3 strings)

Translation: XWiki Rendering/Rendering API
Translate-URL: https://l10n.xwiki.org/projects/xwiki-rendering/rendering-api/mr/

Currently translated at 100.0% (7 of 7 strings)

Translation: XWiki Rendering/Macro transformation
Translate-URL: https://l10n.xwiki.org/projects/xwiki-rendering/macro-transformation/mr/

Currently translated at 100.0% (5 of 5 strings)

Translation: XWiki Rendering/Content Macro
Translate-URL: https://l10n.xwiki.org/projects/xwiki-rendering/content-macro/mr/

* Fix NPE

[Misc] Don't analyze xwiki deps for dependabot (not needed and causing problems with maven properties inherited from parent poms)

XRENDERING-661: Special symbol on its own line within list item is not rendered correctly from XDOM to xwiki/2.1

* Fix jacoco threshold

* Remove unnecessary check (since getChildren() never returns null), thanks Thomas for noticing

* Prefer the manually set heading id over the generated one.
* Add a test case.