Code review comment for ~eslerm/ubuntu-cve-tracker:nvd-api-client

Thank you Alex!

1. Can do.

Could we add `[DEFAULT]` to the top of our teams ~/.ubuntu-cve-tracker.conf environment?

Then the config becomes a valid INI file for the Python builtin configparse: https://wiki.python.org/moin/ConfigParserExamples

2. automagic --since is doable, but I have a concern about --init

The maintenance function searches a time span of modified CVE records. NVD adds metrics after CVE record creation, so --since needs to be set to the most recent lastModified value from the local dataset. Just finding the most recent locally modified file is good enough, even if there is an older lastModified in the local dataset the overlap between them is small.

Their API doesn't document this, but searching a lastModified data of >6 months 404s. I should handle that.

(note that theses API searches download unpublished CVEs. This is acceptable/desired, since the CVE List is the primary source of CVE data which should drive triage. NVD data is supplemental to CVE List data.)

With an automated --init, a misconfigured path could cause 1.3G of API strain to NVD. I added a prompt in the init function to slow down users. Is it okay to keep that? Item X might change the context of --init.

3. That would be helpful :D

I reworked --debug and uncommitted changes look like:

```
./scripts/nvd_api_client.py --since 2023-07-01 --debug
DEBUG: searching for modified NVD CVEs between 2023-07-01T00:00:00.000001%2B00:00 and 2023-08-07T22:01:32.263899%2B00:00
DEBUG: local NVD mirror path is "/home/eslerm/mirrors/nvd"
DEBUG: saved results 0 through 2000 of 4834
DEBUG: saved results 2000 through 4000 of 4834
DEBUG: saved results 4000 through 4834 of 4834
DEBUG: NVD sync complete \o/
```

How does that look?

X. Ideally we should maintain NVD data from a central source to prevent discrepancies. Seth suggested that we may want to explore Canonistack.

Y. I'm hoping this work will also benefit https://github.com/olbat/nvdcve/issues/7