Delete Absoft and Lahey from compilers page

[Beliavsky]

They should be removed from the main section to the discontinued section at https://fortran-lang.org/en/compilers/ since they have been discontinued, according to their web sites.

[Moksh45]

Could you please assign this issue to me? I am eager to help and make the necessary updates to the compilers page.

[192933488S]

Update to documentation required, too, cf. https://fortran-lang.org/learn/os_setup/ides/
Absoft website not available as of today. Wikipedia: "defunct as of 2022"

[TyBalduf]

A few other links on the compiler page could be updated as well:

• NAG: https://nag.com/nag-compiler -> https://nag.com/fortran-compiler/
• ARM: https://developer.arm.com/Tools%20and%20Software/Arm%20Fortran%20Compiler
• HPE/CRAY: https://cpe.ext.hpe.com/docs/#hpe-cray-compiling-environment