Custom UserAgent to Identify saml2aws as a desktop app

[dpreetam]

It would be very helpful if the saml2aws identifies itself as a Desktop app through browser user agent string to EntraID so separate policies can be defined for saml2aws app as a desktop app. This will help define non FIDO2 requirement policy for AWS admin login until a FIDO2 support is enabled in saml2aws.

[mapkon]

This is great. If you can submit a PR, I am happy to review it and merge it

[dpreetam]

My request above was more of an enhancement request. I am not in a position to work on a PR.