Aligned scope param default value with oauth spec

[ch-lepp]

Summary:
Closes #995

Description for the changelog:
The scope params default value is separated by spaces instead of commas as defined by the oauth spec.

[jgadsden]

do not worry about the failed docker build, this is due to a lack of permissions and not to the change

[jgadsden]

thanks for fixing this @ch-lepp , it is very good to have

[ch-lepp]

Thx @jgadsden for reviewing and merging this PR so quickly.

Could you pls also have a look into the discussion I opened here?
I am pretty confused about the correct redirect uri...