Fix pagination not working for `/search` results

[TimJentzsch]

Relevant issue: Closes #163

Description:

While implementing an optimization I accidentally broke the pagination. Instead of caching only responses with multiple pages, it cached only responses with a single page. Thus, when reacting, the message was never in the cache.

Checklist:

• [x] Code Quality
• [x] Pep-8
• [ ] Tests (if applicable)
• [x] Success Criteria Met
• [ ] Inline Documentation
• [ ] Wiki Documentation (if applicable)