Config: mag.iua.idps is used for SAML IDPs

[qligier]

The configuration at mag.iua.idps stores information about the SAML IDPs, not the IUA ones.
This is an issue if we want to support an IUA IDP (for the frontend and clients).

Currently, we have:

mag:
  iua:
    idps:
      hin:
        name: HIN eID
        metadata-url: secret/metadata_hin_test.xml
        renew-url: https://samlservices.test.epr.fed.hin.ch/saml/2.0/renewassertion
        key-alias: saml
        key-password: samlidp
        tls-key-alias: hintls
        tls-key-password: samlidp

I would like to change it to something like:

mag:
  idps:
    saml:
      hin:
        name: HIN eID
        metadata-url: secret/metadata_hin_test.xml
        renew-url: https://samlservices.test.epr.fed.hin.ch/saml/2.0/renewassertion
        key-alias: saml
        key-password: samlidp
        tls-key-alias: hintls
        tls-key-password: samlidp
        expose-iua: true
    iua:
      ehs:
        name: idp-ehealthsuisse
        metadata-url: https://ehealthsuisse.ihe-europe.net/iua-simulator/rest/ch/.well-known
        client-id: abc123