The bug had been there from the start (commit
47a60325ca650e8fc1a291c8655b4297f4de8deb) but only with the switch to
glibc 2.39 did we actually hit it.
* gnu/packages/aux-files/run-in-namespace.c (main): Add terminating zero
on SELF.
Change-Id: If0488f5ca0964d8d7b1666039a7f8bdf7abce111