make CPE matching case-insensitive

[stohrendorf]

Description

This is an attempt to address issue #4663, to make CPE matching case-insensitive.

Addressed Issue

Fixes #4663

Additional Details

Since this touches areas I'm not familiar with, and since the issue is marked with size M, I'm pretty sure I missed quite a lot of things.

Checklist

• I have read and understand the contributing guidelines
• This PR fixes a defect, and I have provided tests to verify that the fix is effective
• This PR implements an enhancement, and I have provided tests to verify that it works as intended
• This PR introduces changes to the database model, and I have added corresponding update logic
• This PR introduces new or alters existing behavior, and I have updated the documentation accordingly

[owasp-dt-bot]

🎉 Snyk checks have passed. No issues have been found so far.

✅ security/snyk check is complete. No issues have been found. (View Details)

[codacy-production]

Coverage summary from Codacy

See diff coverage on Codacy

Coverage variation	Diff coverage
✅ +0.00% (target: -1.00%)	✅ 100.00% (target: 70.00%)

Coverage variation details

	Coverable lines	Covered lines	Coverage
Common ancestor commit (5aa6230)	23973	19374	80.82%
Head commit (5dcdd7f)	23976 (+3)	19377 (+3)	80.82% (+0.00%)

Coverage variation is the difference between the coverage for the head and common ancestor commits of the pull request branch: <coverage of head commit> - <coverage of common ancestor commit>

Diff coverage details

	Coverable lines	Covered lines	Diff coverage
Pull request (#5280)	16	16	100.00%

Diff coverage is the percentage of lines that are covered by tests out of the coverable lines that the pull request added or modified: <covered lines added or modified>/<coverable lines added or modified> * 100%

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[stohrendorf]

I'm still not sure this covers everything. It feels a bit above my head, and I still got the feeling that there are cases where this will not work properly. For example, with the recent changes, I added more changes for the lucene engine, and I'm not sure how to test this properly.