fix for cve_lookup installation RAM usage

[jstucke]

• stream all data during cve_lookup installation in order to fix RAM issues on the CI
• also: refactor bulky add_cve_items method (which got even larger because of the changes)

[codecov-commenter]

Codecov Report

Attention: Patch coverage is 68.08511% with 15 lines in your changes missing coverage. Please review.

Project coverage is 91.80%. Comparing base (2aa83a0) to head (573d6be).

Files with missing lines	Patch %	Lines
...ugins/analysis/cve_lookup/internal/data_parsing.py	38.09%	13 Missing ⚠️
.../analysis/cve_lookup/internal/database/db_setup.py	92.30%	2 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #1306      +/-   ##
==========================================
- Coverage   92.34%   91.80%   -0.55%     
==========================================
  Files         379      378       -1     
  Lines       23465    20986    -2479     
==========================================
- Hits        21669    19266    -2403     
+ Misses       1796     1720      -76     

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.