make_public.py not executable in deb package

in deb package, `/usr/lib/foudationdb/make_public.py` is missing the executable bits.

[The doc](https://apple.github.io/foundationdb/building-cluster.html#make-foundationdb-externally-accessible) advise to execute `sudo /usr/lib/foudationdb/make_public.py` which result is `sudo: /usr/lib/foundationdb/make_public.py: command not found`

Trying to execute it as root without `sudo` leads to

```
# /usr/lib/foundationdb/make_public.py
-bash: /usr/lib/foundationdb/make_public.py: Permission denied
```
indeed, this file from the deb package is not executable

```
# ls -l /usr/lib/foundationdb/make_public.py
-rw-r--r-- 1 root root 4129 sept. 21 2022 /usr/lib/foundationdb/make_public.py
```

Inspect the Debian package entry for /usr/lib/foundationdb/make_public.py and compare its installed mode with the command in the building-cluster documentation. Confirm that the packaged script is executable and that the documented sudo invocation runs without a permission or command-not-found error.

Written by the indexing model from the issue text.