[MUK]: Add datagrid size and variant

[aboungnaseng-ovhcloud]

Description

Summary: Added Size and Variant Testing & Controls for Datagrid Component

Test Coverage Additions

1. Snapshot Tests (Datagrid.snapshot.spec.tsx)

• Added 4 new snapshot tests for size and variant attributes:
  • Small size (TABLE_SIZE.sm)
  • Medium size (TABLE_SIZE.md)
  • Large size (TABLE_SIZE.lg)
  • Striped variant (TABLE_VARIANT.striped)

2. Functional Tests (Datagrid.spec.tsx)

• Created new "Table Styles" test suite with 3 tests:
  • Small size → validates table--sm class
  • Large size → validates table--lg class
  • Striped variant → validates table--striped class
• Applied code formatting improvements (line breaks, spacing)

3. Storybook Controls (datagrid.stories.tsx)

• Added interactive controls in Storybook's control panel:
  • size control: select dropdown with sm/md/lg options
  • variant control: select dropdown with default/striped options

Technical Changes

• Added imports for TABLE_SIZE and TABLE_VARIANT from @ovhcloud/ods-react
• Used className.toContain() assertions to verify correct CSS classes are applied
• Improved code formatting for better readability

Impact

This commit enhances test coverage and improves the developer experience by making size and variant options easily testable and configurable in Storybook.