Proposal:

1) Go back to v7r1 for certifying:

- MySQL 8 (updated already)

- Flags

export DIRAC_DEBUG_DENCODE_CALLSTACK=1
export DIRAC_USE_JSON_DECODE=Yes

- SingularityCE (~easy to test)

- JobParameters on ES

- ElasticSearch 7 (dev to be done, probably)

- Move to MultiVO installation (this needs work - GridPP?)

2) v7r2:

- Include HTTPs

- Include Python 3

Start certification with the above 2 once v7r1 is done