Implement test for each feature (list inside the task)

Implement test for each application.
Tests should be for getting data and checking data with the expected result for:

- [x] cameras with algoritms;
- [ ] users;
- [ ] Inventory;
- [x] #264
- [x] #261
- [ ] Dashboard.

The issue mentions testing for users, Inventory, and Dashboard features. Start by examining the existing test structure in the repository, likely in a 'tests' directory. Look for models or views related to these features to understand the data flow. Write tests that fetch data and compare it to expected results, following patterns from the already implemented tests for cameras and algorithms.

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