RI-RPA| Allow for XC correction in ADMM RI-RPA

[abussy]

This PR is a general upgrade of RPA when ADMM is used. There are 3 main aspects:

1. Previously, any usage of ADMM when doing RPA calculations (switched on with RI_RPA%ADMM) ignored the GGA exchange correction. This simply meant doing HFX in a smaller basis, which is a rather strong approximation. This is now fixed, also for GW.

2. Because ADMM operations in RPA rely on the qs_env%admm_env, it was not possible to do ADMM RPA@PBE, which is arguably the most efficient way of doing RPA. This is now possible (with XC correction) thanks to a small refactoring of general ADMM. This also means that RPA specific xc_section_aux and xc_section_primary sections are created and stored.

3. The RI_RPA%HF input section governing EXX calculations is, in most cases, identical to the DFT%XC%HF section with the exception of the FRACTION keyword. Therefore, efficiency and memory usage can be improved by reusing the HFX data from the qs_env and rescaling. This is now automatically done if the two HF section only differ by the FRACTION keyword (this is also true without ADMM).

New regtests for ADMM RPA@PBE were added and results for ADMM RPA@PBE0 were updated.

[oschuett]

After this PR the CH3_md_periodic_admm.inp test went from 49 to 288 seconds. Ideally, regtests shouldn't run longer than 30 seconds.

[abussy]

#2227 this should fix it

[oschuett]

Thanks @abussy !