Describe the bug
A recent change in v1.9.3 causes the dot file to be copied to the XML output folder. The dot file's path in XML now uses a relative path, where it used to be an absolute path.

This path change is breaking breathe's ability (the sphinx extension) to find the dot file and in turn pass it to the dot tool.

Expected behavior
Please switch back to using an absolute path. I don't care if it points to the copied dot file in the XML folder or the originally specified dot file.

To Reproduce
dot_graphs.zip

Version
1.9.3 (c0b9eaf)

• Ubuntu 64-bit. Installed from archived binary distribution on SourceForge

  Distributor ID:	Ubuntu
  Description:	Ubuntu 21.10
  Release:	21.10
  Codename:	impish
  

• Windows 64-bit. Installed from doxygen website (https://www.doxygen.nl/download.html)

Additional context
I'm currently looking to workaround this problem in the sphinx extension, breathe - paths used for sphinx vs paths used for doxygen might be impossible to resolve effectively. Since this is a version change specific to doxygen, I figured I'd raise the issue here.