Add a new property 'fragment' to be appended to the authorize URL on redirect

[willhackett]

Description

In some circumstances the URL may need to be mutated post-generation. An example use case is adding parameters to the hash (#) part of the URL in order to more safely transmit personally identifiable information.

I've added a new public method to return the URL instead of merely redirecting.

Potential use:

const url = await auth0.buildLoginUrl();
window.location.assign(`${url}#hint=user@auth0.com`);

References

• Docs PR - Add "Build login URL" documentation [DO NOT MERGE] docs#8405
• Fragment Identifier
• URL.hash

Testing

Call the buildLoginUrl method available on Auth0Client.

• This change adds test coverage for new/changed/fixed functionality

Checklist

• I have added documentation for new/changed functionality in this PR or in auth0.com/docs
• All active GitHub checks for tests, formatting, and security are passing
• The correct base branch is being used, if not master

[joshcanhelp]

@willhackett - Appreciate the contribution here and in Docs!

This looks good to me but I'm going to leave this for the platform maintainers to make sure this public API addition makes sense to them.

[willhackett]

@luisrudge if preferred, this is also an option:
88ac957

[stevehobbsdev]

Hey @willhackett, appreciate your patience with this. We'd like to go for option 2 (88ac957). Would you be able to rework the PR (or feel free to raise a new one) with that?

Thanks for the contribution!