PCVL-1148 XXXFockState interface aligned with BasicState#708

Benoit-F-Q wants to merge 2 commits intoQuandela:release/1.2.0Quandela/Perceval:release/1.2.0from

Benoit-F-Q:pcvl_1148_FockState_interfaceBenoit-F-Q/Perceval:pcvl_1148_FockState_interfaceCopy head branch name to clipboard