Vaadin 24: HeightByRowsIT integration tests fail

### Describe the bug

testOpenWithItemsDefaultSize: expected:<10> but was:<9>
testOpenEmptyDefaultSize: expected:<94> but was:<128>
testOpenEmptyFullSize: expected:<94> but was:<128>


### Expected behavior

Integration tests must pass.

### Minimal reproducible example

_No response_

### Add-on Version

2.0.0-SNAPSHOT

### Vaadin Version

24.8.14

### Additional information

_No response_