Review SAML metadata changes

[fhanik]

We noticed that the ID attribute of the SAML metadata changed between two versions of the UAA.

When setting entityID=https://localhost:443 in the UAA configuration file (uaa.yml setting login.entitytID)

UAA 77.19.0

ID="https___localhost_443" entityID="https://localhost:443"

UAA 77.23.0

ID="https://localhost:443" entityID="https://localhost:443"

The ID attribute should be a NCName and not contain colons
https://www.datypic.com/sc/xsd/t-xsd_ID.html (type="ID")

I'm opening this issue to track if other changes have occurred, and if we need to be backwards compatible

[strehle]

From https://cloudfoundry.slack.com/archives/C03FXANBV/p1736193268857739?thread_ts=1732612889.604019&cid=C03FXANBV

Signature value contains line breaks, see
https://stackoverflow.com/questions/4728300/how-to-produce-xml-signature-with-no-whitespaces-and-line-breaks-in-java