Update test to use camelCase field names for CTA button

The CTA component was updated to use camelCase field names (buttonText,
buttonHref) to match the API response format. This updates the test to
use the same field names.

Fixes test failures in body-units.test.tsx

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Sonnet 4.5 <[email protected]>

Author: OpenStaxClaude

test/src/components/body-units.test.tsx

@@ -47,16 +47,15 @@ describe('body-units', () => {
         screen.getByText('terrible mistake', {exact: false});
     });
     it('handles CTA', () => {
-        /* eslint-disable camelcase */
         const unit: UnitType = {
             id: 'meh',
             type: 'blog_cta',
             value: {
                 alignment: 'left',
                 heading: 'Heading',
                 description: 'description text',
-                button_href: '#',
-                button_text: 'click me'
+                buttonHref: '#',
+                buttonText: 'click me'
             }
         };