Fix version fluidsim-core to 0.8.4

fluidsim-core 0.8.3

Set version fluidsim-core to 0.8.2

Merge branch 'topic/default/fix-ci-ga' into 'branch/default'

CI: less Makefile and more Nox

See merge request fluiddyn/fluidsim!374

Merge branch 'topic/default/prepare-0.8.0' into 'branch/default'

Finally v0.8.0

See merge request fluiddyn/fluidsim!371

Merge branch 'topic/default/prepare-0.8.0rc3' into 'branch/default'

Topic/default/prepare 0.8.0rc3

See merge request fluiddyn/fluidsim!370

Merge branch 'topic/default/prepare-0.8.0rc2' into 'branch/default'

v0.8.0rc2

See merge request fluiddyn/fluidsim!369

Merge branch 'topic/default/prepare-0.8.0rc1' into 'branch/default'

v0.8.0rc1 + fix PyPI upload from CI

See merge request fluiddyn/fluidsim!368

Merge branch 'topic/default/prepare-0.8.0' into 'branch/default'

Prepare 0.8.0rc0

See merge request fluiddyn/fluidsim!367

Merge branch 'topic/default/prepare-0.7.4' into 'branch/default'

Prepare 0.7.4

See merge request fluiddyn/fluidsim!343