b4 fails filter-repo with FileNotFoundError

Hi,

I'm seeing this with a few commands, I think at least "b4 trailers -u" 
and "b4 prep --edit-cover". Linux mint, b4 0.15.2.

$ b4 prep --edit-cover
Invoking git-filter-repo to update the cover letter.
New history written in 0.07 seconds...
Traceback (most recent call last):
   File "/home/tomba/.local/bin/b4", line 6, in <module>
     sys.exit(cmd())
              ^^^^^
   File 
"/home/tomba/.local/share/pipx/venvs/b4/lib/python3.12/site-packages/b4/command.py", 
line 512, in cmd
     cmdargs.func(cmdargs)
   File 
"/home/tomba/.local/share/pipx/venvs/b4/lib/python3.12/site-packages/b4/command.py", 
line 85, in cmd_prep
     b4.ez.cmd_prep(cmdargs)
   File 
"/home/tomba/.local/share/pipx/venvs/b4/lib/python3.12/site-packages/b4/ez.py", 
line 3145, in cmd_prep
     return edit_cover()
            ^^^^^^^^^^^^
   File 
"/home/tomba/.local/share/pipx/venvs/b4/lib/python3.12/site-packages/b4/ez.py", 
line 885, in edit_cover
     store_cover(new_cover, tracking)
   File 
"/home/tomba/.local/share/pipx/venvs/b4/lib/python3.12/site-packages/b4/ez.py", 
line 749, in store_cover
     run_frf(frf)
   File 
"/home/tomba/.local/share/pipx/venvs/b4/lib/python3.12/site-packages/b4/ez.py", 
line 157, in run_frf
     frf.run()
   File 
"/home/tomba/.local/share/pipx/venvs/b4/lib/python3.12/site-packages/git_filter_repo.py", 
line 4936, in run
     self._record_metadata(self.results_tmp_dir(), self._orig_refs)
   File 
"/home/tomba/.local/share/pipx/venvs/b4/lib/python3.12/site-packages/git_filter_repo.py", 
line 4767, in _record_metadata
     self._compute_metadata(metadata_dir, orig_refs)
   File 
"/home/tomba/.local/share/pipx/venvs/b4/lib/python3.12/site-packages/git_filter_repo.py", 
line 4648, in _compute_metadata
     with open(os.path.join(metadata_dir, b'first-changed-commits'), 
'br') as f:
          ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
FileNotFoundError: [Errno 2] No such file or directory: 
b'/home/tomba/work/linux/.git/worktrees/linux-renesas/filter-repo/first-changed-commits'

I'm not sure if this is related to working under 
"[email protected]" email when in linux-renesas 
directory, as I don't see this on my "normal" linux tree. Then again, I 
think "b4 prep --edit-cover" was working fine on linux-renesas earlier 
today (but "b4 trailers -u" was failing), but now both edit-cover and 
trailers is giving this error.

  Tomi