PADV-1511 - Add setting to store SAML IDP id values.

[Squirrel18]

Description:

This PR adds a new setting called: SAML_IES_ENTITIES_IDS to configure the values of the IES SAML IDP ids for stage and prod. Initially we avoided this approach, but due to some problems with the IES configuration, it is better to do it this way so that we can quickly change the values in case we need to change them.

How to test:

• Set up a local SAML IDP, check this video about SAML and configuring a local IDP: https://youtu.be/1PoWSVtwheI
• Create a test account on the IDP, follow this: https://github.com/kenchan0130/docker-simplesamlphp?tab=readme-ov-file#customize-idp-users
• Remove the fullname attribute associated with the IDP user.
• Add the entity id uri to the list of: SAML_IES_ENTITIES_IDS
• In a private window, log in using the local IDP.
• You should be logged in automatically and the fullname attribute should be set to your provided name + last name.

Notes:

We will store the actual values using the Tutor Plugin.

Reviewers:

• @anfbermudezme