Fail early if ZIM cannot be created at given location / name

[benoit74]

Currently, if given output location or ZIM name are incorrect, we fail very late, after all stuff has been scraped.

We should fail way earlier.

We should use openzim/python-scraperlib#163 (once implemented) for these checks.

Playlist mode where ZIM name is dynamically computed is probably going to be a bit more complex / not possible, but we will live without that (especially since anyway we do not use playlist mode in Zimfarm anymore)

[benoit74]

3.4.0 has been released, we now need to use the utility in our codebase