fix(authproxy): set openshift oauth proxy prefix to match oauth2_proxy prefix

[andrewazores]

Fixes cryostatio/cryostat#365
Depends on cryostatio/cryostat#366

$ cat htpasswd.conf 
user:$2y$05$Ju.w7ibNuQ/xaAfKH74lJOJ5xqZbONaNWf7HnrjQuZP.4nhLrr0uS

$ oc create secret generic basicauth --from-file=htpasswd.conf

$ helm install cryostat \
--set authentication.openshift.enabled=true \
--set core.route.enabled=true \
--set openshiftOauthProxy.image.repository=quay.io/andrewazores/openshift-oauth-proxy \
--set openshiftOauthProxy.image.tag=test-14 \
--set authentication.basicAuth.enabled=true \
--set authentication.basicAuth.secretName=basicauth \
--set authentication.basicAuth.filename=htpasswd.conf \
--set core.image.repository=quay.io/andrewazores/cryostat \
--set core.image.tag=3.0.0-oauth-signout-1 \
./charts/cryostat/

It's a bit of a long incantation for testing this, but it's because OpenShift auth must be enabled, I also enable basic auth to test that second case, and then until cryostatio/cryostat#366 is merged it must be tested with a custom Cryostat image, and it must also be tested with a custom oauth-proxy image until openshift/oauth-proxy#272 is addressed.

After that, you should be able to open the Cryostat UI. You will first be greeted by the openshift-oauth-proxy login screen. Log in via htpasswd with user:pass. You should see the actual Cryostat UI. Click the user icon and Logout in the masthead. You should be returned to the login screen - refreshing the page should leave you on the login screen. Next try logging in with OpenShift SSO. This should work largely the same way, but use your OpenShift account credentials instead of user:pass.

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Odd bug: if you don't also enable the htpasswd Basic auth mechanism and leave it on OpenShift SSO only, then the logout does not fully work due to a CORS issue.

However after pressing the Logout button all UI requests fail (because you are actually logged out), and if you try to refresh the page then you will land on the OpenShift SSO login agin.

See cryostatio/cryostat-web#1237 for the bugfix.

[andrewazores]

Maybe a hackish workaround for the bug above would be to just force a refresh on the web-client side if it looks like there was a request failure?