Fix CILogon redirect

[laperlej]

When galaxy redirects to CILogon, it passes a query parameter called idphint which is usually a url starting with https://.

Starting at 24.1 the axios calls in the ExternalLogin.vue were changed to use withPrefix from utils/redirect.ts. The problem is that this strips all double slashes, invalidating any protocol passed as parameters (https:// becomes http:/)

I added a test to ensure that CILogon redirects are done correctly and changed the regex to only match duplicate slashes that are not preceded by a colon.

How to test the changes?

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• I've included appropriate automated tests.
• This is a refactoring of components with existing test coverage.
• Instructions for manual testing are as follows:
  1. [add testing steps and prerequisites here if you didn't write automated tests covering all your changes]

License

• I agree to license these and all my past contributions to the core galaxy codebase under the MIT license.

[davelopez]

Thank you @laperlej!

Can you target the release_24.1 branch since this is a bug fix for that version?