feat: add configuration for JWK URL (reanahub#741)

Author: tomondre

reana_server/config.py

@@ -346,6 +346,8 @@ def _get_rate_limit(env_variable: str, default: str) -> str:
     OAUTHCLIENT_REMOTE_APPS["keycloak"] = KEYCLOAK_APP
     OAUTHCLIENT_REST_REMOTE_APPS["keycloak"] = KEYCLOAK_REST_APP
 
+    REANA_OAUTH_JWK_URL = PROVIDER_CONFIG.get("jwk_url", "")
+
 # CERN SSO configuration
 OAUTH_REMOTE_REST_APP = copy.deepcopy(cern_openid.REMOTE_REST_APP)
 OAUTH_REMOTE_REST_APP.update(