Fix recursion error in tox for allowlist_externals.

On GHA it was fine, but locally it was failing for me:

```
tox.report.HandledError: replace failed in py312.allowlist_externals with RecursionError('maximum recursion depth exceeded')
```

Might depend on the tox version.

Author: mauritsvanrees

tox.ini

@@ -17,4 +17,4 @@ deps =
     pytest-cov
 allowlist_externals =
     cp
-    {envsitepackagesdir}/i18ndude/tests/tox-check-i18ndude-command.sh
+    */i18ndude/tests/tox-check-i18ndude-command.sh