all_portal_links: set as allowed faiulre when responds with429

[pcrespov]

• rephrase MSG_TOO_MANY_GUESTS
• mark e2e this test as allowed failure if received HTTP_429_TOO_MANY_REQUESTS

SeE
https://github.com/itisfoundation/osparc-simcore/blob/66d69a6843071547cb0b355150e301a7307aedcf/services/web/server/src/simcore_service_webserver/studies_dispatcher/_studies_access.py

[mrnicegyu11]

The plan is to propagate a 429 rate-limiting status code through puppeteer (p2e is still puppeteer) to the exit-code of the node process that runs in the gitlab CI, and have the gitlab CI accept this process exit code as "allowed failure".

FYI: In Linux, process exit codes range from 0 to 255. Values above 255 wrap around modulo 256, meaning exit code 256 would be seen as 0. So we must make gitlab accept the unix exit code 429 mod 256 = 173 as allowed-failure.

Todo:

• Address .gitlab-ci.yml: PR prepared here: https://git.speag.com/oSparc/e2e-portal-testing/-/merge_requests/39
• Make puppeteer raise 429 REST status code as its own exit code
• Have osparc errors give the correct REST status code: REST response status code of osparc errors are 302 instead of 5xx #6477