Ownership change for DOM, XSLT and XML modules

Hi,

As I am not going to be involved as much with Mozilla anymore, I'd
like to announce the following changes to the modules that I was the
owner of:

I am pleased to announce that Andrew McCreight is now the module
owner for the "Core: DOM" module. Andrew has been
a peer of the module since 2018, has been involved as a developer in
Mozilla for much longer and has also been essential in organizing
triage of DOM security bugs. Congratulations Andrew!

I am also pleased to announce that Henri Sivonen and Andrew McCreight
are now co-owners of the "Core: XML" module. This module mainly deals
with the XML parser. Henri has been working on the HTML parser and the
interfaces between the parser and the DOM for more than 15 years. Andrew
has been helping me lately with keeping the Expat parser updated.
Congratulations Henri and Andrew!

The DOM peers have also been discussing the future of the "Core:
XSLT Processor" module, that I also am the owner of (without any
remaining peers). Because this module covers code that is essentially in
maintenance mode, we think it makes the most sense to just fold it
into the "Core: DOM" module, since anyone working on that
maintenance will most likely be a peer of the "Core: DOM" module.

Peter