Added support for headerRowClass.

[Agent009]

Works similar to rowClass but gets applied on the header row.

<DataGrid ... rowClass={rowClass} headerRowClass={headerRowClass} />

[amanmahajan7]

Can we not target header row with a grid class?

<DataGrid className="custom-header" ... />

.custom-header > .rdg-header-row {
  ...
}

[Agent009]

Can we not target header row with a grid class?

<DataGrid className="custom-header" ... />

.custom-header > .rdg-header-row {
  ...
}

Can do, but that doesn't allow for using pre-defined classes from other systems such as Tailwind. The dedicated property was added to cater for this.

[amanmahajan7]

Can you resolve the conflicts and add a test and we can merge this PR

[codecov[bot]]

Codecov Report

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

Project coverage is 98.69%. Comparing base (5a2c4d9) to head (ef73b0b). Report is 2 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #3405      +/-   ##
==========================================
- Coverage   98.80%   98.69%   -0.12%     
==========================================
  Files          47       47              
  Lines        3444     3451       +7     
  Branches      749      749              
==========================================
+ Hits         3403     3406       +3     
- Misses         41       45       +4     

Files with missing lines	Coverage Δ
src/DataGrid.tsx	99.77% <100.00%> (+<0.01%)	:arrow_up:
src/HeaderRow.tsx	100.00% <100.00%> (ø)

... and 1 file with indirect coverage changes

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[amanmahajan7]

Thank you for the PR