Add `ratio_max` for presampling strategies

[MaxiBoether]

I realized we also need to set ratio_max for presampling strategies, otherwise they cannot run 12.5% as well.

[codecov[bot]]

Codecov Report

Attention: Patch coverage is 87.50000% with 1 line in your changes missing coverage. Please review.

Project coverage is 82.31%. Comparing base (4d78544) to head (2be4ea6).

Files	Patch %	Lines
modyn/config/schema/pipeline/sampling/config.py	83.33%	1 Missing :warning:

Additional details and impacted files

```diff @@ Coverage Diff @@ ## main #544 +/- ## ======================================= Coverage 82.30% 82.31% ======================================= Files 217 217 Lines 10118 10125 +7 ======================================= + Hits 8328 8334 +6 - Misses 1790 1791 +1 ```

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