bitops.config.yaml should be validated against the schema

Following the https://github.com/bitovi/bitops/pull/236
While having a config schema, looks like we don't do a proper validation for plugins config `bitops.config.yaml`.

Example nonsense yaml config:
```yaml
bitops:
a: b
c: d
fail_fast: true
d:
e
logging:
level: foo
color:
enabled: maybe
```

Should be validated properly against the config schema and error in every place with a clear error message as users will naturally create typos, wrong copy-paste or invalid configs and the error messages they might get now are confusing.