By providing a refresh token, obtained with the `swh authentication login`
command to the new `authenticate` method of the client, all emitted requests
will be authenticated using a bearer token sent in headers.
Example of use:
```lang=python
from swh.web.client import WebAPIClient
REFRESH_TOKEN = '.......' # Use "swh authentication login" command to get it
client = WebAPIClient()
client.authenticate(REFRESH_TOKEN)
# All requests to the Web API will be authenticated
resp = client.get('swh:1:rev:aafb16d69fd30ff58afdd69036a26047f3aebdc6')
```
Depends on D2861
Related to T1927