MudDataGrid: remove detrimental ChildRowContent CSS

[versile2]

Description

DataGrid uses CSS to alter the mud-input's it is using for it's cell and cell editing functions. I introduced a css class that ignores the margin portion of that style mud-table-child-content . I applied that class to the two places in the razor file it absorbs ChildRowContent. Also anytime a dev wants to use a mudtextfield with label they can now just add mud-table-child-content to the CellClass and it will not scrunch the settings.
Resolves #10351

How Has This Been Tested?

Visually, unit tests still operate. Before and After in first comment.

Type of Changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• Documentation (fix or improvement to the website or code docs)

Checklist

• The PR is submitted to the correct branch (dev).
• My code follows the code style of this project.
• I've added relevant tests.

[versile2]

Before

After

[ScarletKuro]

Please, add before and after pic.

[versile2]

Please, add before and after pic.

before and after in first comment?

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud

[danielchalmers]

Will review after v8 is out