Fixes interactive mode for cvss v4.0

[chrisdlangton]

addresses #47

[chrisdlangton]

FYI
No tests existed for interactive mode, for me to update.
Searched for imports using repo:RedHatProductSecurity/cvss path:/^tests\// interactive

[jsvob]

The calculator doesn't return a CVSS v4.0 score in either non-interactive and interactive mode.

$ cvss_calculator -4 -v "CVSS:4.0/AV:P/AC:H/AT:P/PR:H/UI:A/VC:L/VI:L/VA:L/SC:L/SI:L/SA:L/S:N"
Traceback (most recent call last):
  File "/TMP/cvss/venv/bin/cvss_calculator", line 8, in <module>
    sys.exit(main())
             ^^^^^^
  File "/TMP/cvss/venv/lib64/python3.11/site-packages/cvss/cvss_calculator.py", line 63, in main
    scores = cvss_vector.scores()
             ^^^^^^^^^^^^^^^^^^
AttributeError: 'CVSS4' object has no attribute 'scores'

[chrisdlangton]

Should be working now, CVSS4 methods weren't API backwards compatible

[jsvob]

LGTM with a minor nitpick. Thank you!