Link in sample config file pointing to djanjo website is invalid

Line 60 of the "[settings_local.sample.py](https://github.com/fsinfuhh/Bitpoll/blob/master/bitpoll/settings_local.sample.py)" config fle points to an old link "https://docs.djangoproject.com/en/1.9/ref/settings/#databases" which seem to be obsolete. Just guessing but "https://docs.djangoproject.com/en/5.1/ref/databases/" might be what should be the reference here.