NetBox should always be referred to as NetBox

Fix all instances of "Netbox".

```Shell
git ls-files -z . | xargs --null -I '{}' find './{}' -type f -print0 | xargs --null sed --in-place --regexp-extended 's#Netbox#NetBox#g;'
```

Ref: https://netbox.readthedocs.io/en/stable/development/style-guide/#branding

docker/docker-entrypoint.sh

@@ -1,10 +1,10 @@
 #!/bin/bash
-# Runs on every start of the Netbox Docker container
+# Runs on every start of the NetBox Docker container
 
 # Stop when an error occures
 set -e
 
-# Allows Netbox to be run as non-root users
+# Allows NetBox to be run as non-root users
 umask 002
 
 # Load correct Python3 env