refactor(descriptions): remove pkg/descriptions and related CLI flag

[cx-ricardo-jesus]

Reason for Proposed Changes

• Currently the descriptions package, does not fetch any cis_descriptions.

Proposed Changes

• Removed E2E test 046, since the purpose of this unit test is to simulate the --disable-full-descriptions, flag doesn't make sense to have it since the descriptions package has been removed.
• Renamed the E2E tests to be ordered, since one of them was removed.
• Removed any reference to the --disable-full-descriptions flag on kics documentation.
• Fully removed pkg/descriptions.
• Implemented a new function inside pkg/scan/client.go that checks if the current KICS version is up-to-date by querying the GitHub releases API. It early returns assuming it's the latest if the version is "development", an HTTP request fails, a 404 response is returned, or other errors occur reading the API response. Otherwise compares the local version against the tag_name from the release response.

I submit this contribution under the Apache-2.0 license.