remove duplicate oois from report

[noamblitz]

Changes

Removes duplicate oois from report from report requests like:

http://localhost:8000/en/as/reports/generate-report/view/?observed_at=2024-02-14&ooi=Hostname%7Cinternet%7Cmispo.es&ooi=Hostname%7Cinternet%7Cmispo.es&clearance_level=2&clearance_level=3&clearance_level=4&clearance_type=declared&plugin=nmap&plugin=dns-records&report_type=systems-report

Issue link

Closes #2503

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Code Checklist

• All the commits in this PR are properly PGP-signed and verified.
• This PR only contains functionality relevant to the issue; tickets have been created for newly discovered issues.
• I have written unit tests for the changes or fixes I made.
• For any non-trivial functionality, I have added integration and/or end-to-end tests.
• I have performed a self-review of my code and refactored it to the best of my abilities.

Communication

• I have informed others of any required .env changes files if required and changed the .env-dist accordingly.
• I have made corresponding changes to the documentation, if necessary.
• I have included comments in the code to elaborate on what is not self-evident from the code itself, including references to issues and discussions online, or implicit behavior of an interface.

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Checklist for code reviewers:

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Checklist for QA:

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