Filter results of OSSI scan by score, fixes #261

[timkpaine]

Allows the setting of a minimum vulnerability score threshold, to filter out relatively minor reports. Done for FINOS project usage, to replace my current hack: https://github.com/timkpaine/auditjs-screener. @maoo

This pull request makes the following changes:

• add an arg to ossi to specify a minimum score threshold, defaults to 0 to match current behavior

It relates to the following issue #s:

• Fixes [FEATURE] Filtering vulnerabilities by score #261

cc @bhamail / @DarthHater / @allenhsieh / @ken-duck

Note: I looked for a place to add tests but didn't see a good spot to do so. Here is an example run on auditjs itself

[ timkpaine@mbp-m1 ]: node bin/index.js ossi -q -s 3.6
[1/1] - pkg:npm/[email protected] - 1 vulnerability found!

  Vulnerability Title:  1 vulnerability found
  ID:  sonatype-2022-3677
  Description:  1 non-CVE vulnerability found. To see more details, please create a free account at https://ossindex.sonatype.org/ and request for this information using your registered account
  CVSS Score:  3.7
  CVSS Vector:  CVSS:3.1/AV:A/AC:H/PR:N/UI:R/S:U/C:L/I:L/A:N
  Reference:  https://ossindex.sonatype.org/vulnerability/sonatype-2022-3677

[ timkpaine@mbp-m1 ]: node bin/index.js ossi -q -s 3.8


[ timkpaine@mbp-m1 ]: