Add [DisallowNull] on TId in pipeline parameters

[bkoelman]

Fixes #1571.

QUALITY CHECKLIST

• [x] Changes implemented in code
• [x] Complies with our contributing guidelines
• [x] Adapted tests
• [ ] N/A: Documentation updated

[codecov[bot]]

Codecov Report

All modified and coverable lines are covered by tests :white_check_mark:

Project coverage is 90.80%. Comparing base (ae5d0d1) to head (3897ebd).

Additional details and impacted files

```diff @@ Coverage Diff @@ ## master #1583 +/- ## ======================================= Coverage 90.80% 90.80% ======================================= Files 348 348 Lines 11184 11185 +1 Branches 1836 1836 ======================================= + Hits 10156 10157 +1 Misses 676 676 Partials 352 352 ```

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