Missing configuration options result in unclear, uncaught error messages

[C0rn3j]

It would be nice if these config issues were caught with a human readable error thrown back, the current error with this wrong config made me think downstream pkgctl wasn't using the config correctly.

# Wrong config I tried to use that throws the problematic error message
# git = is not needed to repro
[vtracer]
source = "github"
git = "https://github.com/visioncortex/vtracer.git"

# Working config, just to be clear
[vtracer]
source = "github"
github = "visioncortex/vtracer"
use_latest_release = true

% nvchecker -c nvchecker.toml
[E 11-04 20:37:09.918 core:369] vtracer: unexpected error happened error=KeyError('github')
    Traceback (most recent call last):
      File "/usr/lib/python3.12/site-packages/nvchecker/util.py", line 311, in run_one
        version = await self.func(
                  ^^^^^^^^^^^^^^^^
      File "/usr/lib/python3.12/site-packages/nvchecker_source/github.py", line 39, in get_version
        return await get_version_real(name, conf, **kwargs)
               ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
      File "/usr/lib/python3.12/site-packages/nvchecker_source/github.py", line 158, in get_version_real
        repo = conf['github']
               ~~~~^^^^^^^^^^
    KeyError: 'github'
[E 11-04 20:37:09.919 core:447] vtracer: no-result error="'github'"

nvchecker/nvchecker_source/github.py

Line 164 in 28f1ab5

repo = conf['github']

[lilydjwg]

Yes, the latter error message is quite confusing. I'm changing str(e) to repr(e) as some builtin Python exceptions has such messages.

A better way to handle this is to validate the config file via a schema, but that's a lot of work to do...