20260602 - Support for SAML Auth for Global Protect endpoints

• Updated Ubuntu
• New support for SAML Auth for Global Protect endpoints (with gateway discovery)
• Split of images (The main "plain" variant with support for plain u/p auth, and another variant that supports SAML auth.) The plain image remains very small. The SAML image requires a bit more support. Refer to the updated README for how to use the SAML version and how to log in to the endpoint using the built-in web browser.

20240901

First release for Docker Hub.