Fix enum values for Python 3.11+

[tcompa]

A current example may look like

1744197970_TaskGroupActivityActionV2.COLLECT_5_get_venv_size_and_file_number.sh

while it should not include the TaskGroupActivityActionV2 part.

[tcompa]

Ref e.g. https://github.com/fractal-analytics-platform/fractal-server/blob/14cd578df99913dbd2818efc444a0abcf83ef90f/fractal_server/tasks/v2/ssh/collect.py#L169C15-L169C16

[tcompa]

This is due to a change in Enums in Python3.11:

• Enum with str or int Mixin Breaking Change in Python 3.11 python/cpython#100458

It is a minor issue for this specific case, but we should review wether we are using the TaskGroupActivityActionV2.COLLECT pattern in places where we really need the value to be collect.

---

Also, when we deprecate Python3.10 we should also rely on StrEnum:

from enum import Enum, StrEnum

class ColorsOld(Enum):
    RED = "red"
    YELLOW = "yellow"


class ColorsNew(StrEnum):
    RED = "red"
    YELLOW = "yellow"

print(ColorsOld.RED)
print(ColorsNew.RED)

$ python3.11 example.py 
ColorsOld.RED
red

[tcompa]

• Use .value when building filenames
• Review of all Enum-based comparisons in endpoints. For all Enum classes we have, grep for equality/inequality comparisons and see that they all follow the same pattern - and test that pattern in an isolated example.
• Revert addition of .value after switching to StrEnum