Error when creating user config for the first time

### Steps to reproduce

1. Have a fresh installation of speech dispatcher or a fresh user account or delete your `~/.config/speech-dispatcher` folder
2. Run `spd-conf` as user with any configuration (default values are fine)

### Obtained behavior

Instead of saving the file at the end, speech-dispatcher errors out:
```
$ spd-config
[…]
>
Default speech pitch range (on the scale of -100..100, 0 is default, 50 is higher, -50 is lower) [0] :
>
Traceback (most recent call last):
File "/usr/bin/spd-conf", line 26, in
sys.exit(speechd_config.main())
File "/usr/lib64/python3.10/site-packages/speechd_config/config.py", line 841, in main
configure.complete_config()
File "/usr/lib64/python3.10/site-packages/speechd_config/config.py", line 754, in complete_config
self.configure_basic_settings(type='user')
File "/usr/lib64/python3.10/site-packages/speechd_config/config.py", line 673, in configure_basic_settings
self.options_substitute(configfile,
File "/usr/lib64/python3.10/site-packages/speechd_config/config.py", line 549, in options_substitute
for line in fileinput.input(configfile, inplace=True, backup=".bak"):
File "/usr/lib64/python3.10/fileinput.py", line 256, in __next__
line = self._readline()
File "/usr/lib64/python3.10/fileinput.py", line 357, in _readline
os.rename(self._filename, self._backupfilename)
FileNotFoundError: [Errno 2] Datei oder Verzeichnis nicht gefunden: '/home/[username]/.config/speech-dispatcher/speechd.conf' -> '/home/[username]/.config/speech-dispatcher/speechd.conf.bak'
```

### Expected behavior

Save file at end of following configuration wizard `spd-conf`.

### Behavior information

(does not apply as this is not a bug in the speech-dispatcher daemon)

### Distribution

Fedora 36

### Version of Speech-dispatcher

```
speech-dispatcher-0.11.1-2.fc36.x86_64
speech-dispatcher-espeak-ng-0.11.1-2.fc36.x86_64
speech-dispatcher-utils-0.11.1-2.fc36.x86_64
speech-dispatcher-flite-0.11.1-2.fc36.x86_64
```

### Additional notes

I think (but I am not 100% sure) that this issue is the same as #649 which hasn't been fixed completely. That fix has landed in the 0.11.1 release (which I'm running) as far as I understand [from the git history of 0.11 branch](https://github.com/brailcom/speechd/commits/speech-dispatcher-0-11).

I think, the actual cause of the traceback is different: The file `~/.config/speech-dispatcher/speechd.conf` does not exist on a fresh installation or after deleting `~/.config/speech-dispatcher`. When `fileinput.input()` is called on that code, the `fileinput` module relies on the existence of that file and tries to rename it using `os.rename()` ([source code](https://github.com/python/cpython/blob/9369942054fe3fe389f4f4ff808d33c5d7945052/Lib/fileinput.py#L171)).

If I understand the issue correctly, there should be some code creating¹ that file if it does not exist yet. That code should probably be placed at the beginning of [`options_substitute`](https://github.com/brailcom/speechd/blob/master/src/api/python/speechd_config/config.py#L534) before calling `fileinput.input()`.

_____
¹ or copying from the default config file. I don't know the code well enough to tell.

Start in src/api/python/speechd_config/config.py at options_substitute, then follow how spd-conf handles a fresh user configuration. Reproduce with a fresh installation or without ~/.config/speech-dispatcher/speechd.conf. Done means the wizard completes and saves the user configuration without the fileinput traceback.

Written by the indexing model from the issue text.