[#386] Checks for selectielijstklasse waardering "blijvend bewaren" [Backend]

[SilviaAmAm]

Partially fixes #386

[codecov-commenter]

Codecov Report

Attention: Patch coverage is 95.23810% with 5 lines in your changes missing coverage. Please review.

Project coverage is 76.52%. Comparing base (17687ca) to head (c5ae7d1). Report is 5 commits behind head on main.

Files with missing lines	Patch %	Lines
...s/e2e/features/test_feature_list_process_review.py	25.00%	3 Missing :warning:
...c/openarchiefbeheer/destruction/api/serializers.py	96.66%	1 Missing :warning:
backend/src/openarchiefbeheer/zaken/utils.py	91.66%	1 Missing :warning:

Additional details and impacted files

```diff @@ Coverage Diff @@ ## main #389 +/- ## ========================================== - Coverage 76.75% 76.52% -0.23% ========================================== Files 243 245 +2 Lines 7628 7780 +152 Branches 160 171 +11 ========================================== + Hits 5855 5954 +99 - Misses 1624 1669 +45 - Partials 149 157 +8 ``` | [Flag](https://app.codecov.io/gh/maykinmedia/open-archiefbeheer/pull/389/flags?src=pr&el=flags&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=maykinmedia) | Coverage Δ | | |---|---|---| | [](https://app.codecov.io/gh/maykinmedia/open-archiefbeheer/pull/389/flags?src=pr&el=flag&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=maykinmedia) | `76.52% <95.23%> (-0.23%)` | :arrow_down: | Flags with carried forward coverage won't be shown. [Click here](https://docs.codecov.io/docs/carryforward-flags?utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=maykinmedia#carryforward-flags-in-the-pull-request-comment) to find out more.

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