Fix MYSQL_PORT

[filipfigzalski]

I've got following error when trying to set up this container:

seafile-1  | Traceback (most recent call last):
seafile-1  |   File "/scripts/start.py", line 95, in <module>
seafile-1  |     main()
seafile-1  |   File "/scripts/start.py", line 59, in main
seafile-1  |     init_seafile_server()
seafile-1  |   File "/scripts/bootstrap.py", line 166, in init_seafile_server
seafile-1  |     call('{} auto -n seafile'.format(setup_script), env=env)
seafile-1  |   File "/scripts/utils.py", line 70, in call
seafile-1  |     return subprocess.check_call(*a, **kw)
seafile-1  |   File "/usr/lib/python3.10/subprocess.py", line 364, in check_call
seafile-1  |     retcode = call(*popenargs, **kwargs)
seafile-1  |   File "/usr/lib/python3.10/subprocess.py", line 345, in call
seafile-1  |     with Popen(*popenargs, **kwargs) as p:
seafile-1  |   File "/usr/lib/python3.10/subprocess.py", line 971, in __init__
seafile-1  |     self._execute_child(args, executable, preexec_fn, close_fds,
seafile-1  |   File "/usr/lib/python3.10/subprocess.py", line 1783, in _execute_child
seafile-1  |     env_list.append(k + b'=' + os.fsencode(v))
seafile-1  |   File "/usr/lib/python3.10/os.py", line 811, in fsencode
seafile-1  |     filename = fspath(filename)  # Does type-checking of `filename`.
seafile-1  | TypeError: expected str, bytes or os.PathLike object, not int

For some reason MYSQL_PORT was cast to int.

[kirisakow]

Related: #373

[freeplant]

It should have been fixed already.