docs: typo fix
docs: typo fix

Signed-off-by: Lars Holm Nielsen <7eaffca9f7cd98839b5821d0d23e09ff764b82cd@cern.ch>
inveniosoftware/invenio-oauthclient,tiborsimko/invenio-oauthclient,tiborsimko/invenio-oauthclient,inveniosoftware/invenio-oauthclient,tiborsimko/invenio-oauthclient,inveniosoftware/invenio-oauthclient