fix: really disable ssl warnings in console

[ndom91]

• Enable hiding the urllib3 warnings if ignore_ssl env var is enabled. Previously, when that env var option is enabled the import would work, but the output would be flooded with urllib3 warnings making the normal output almost unreadable.
• Remove "tested with.." note from README, just leads to confusion and is difficult to keep up-to-date. Just ran this with 3.7.0 and it successfully updated some device-types, imported new device-types, and even added images to some existing device-types. So I'd say its fine for the latest version of Netbox as well.

[daryll-swer]

@ndom91 Can the SSL warning issue be “resolved” instead of just suppressing the warnings? Perhaps with latest version of urllib3?

This seems to suggest a “bug free” version (presumably latest version 2.1.0), resolves the actual issue.