[BUG] jammy: Use of multi-origin sources leaves some room for issues with source names

[cpuguy83]

Currently jammy uses multi-origin sources when building the deb packages.
For reference: multi-origin is the practice of splitting sources into separate tarballs and creating an empty "orig" tarball (see the deb packaging layout for more details here).

Multi-orig tarballs have stricter naming requirements and as such we've had to sanitize source names which will probably work most of the time, but really the sanitization we have is bug-prone.
e.g., a source named foobar and foo-bar will almost certainly collide when building a deb package with dalec b/c the sanitization we did just strips forbidden characters.

I suggest we switch this strategy to just merge all the sources into one tarball with the desired layout.