[Documentation]: Update OOD docs

### What documentation issue are you reporting

Incorrect Documentation

### Issue

Update docs under 'docs/safe-haven-services/open-ondemand':
* Replace use of term 'TRE' with 'SHS'/'Safe Haven Services'
* Reset OOD as 'SHS Application Services;'.

Update images in `docs/images/open-ondemand/` to reflect current look-and-feel.