Update headings: Introduction page

[oddball-lindsay]

Accessibility has flagged issues with the headings on our /introduction page.

Expected vs. Actual

Expected: Headings should match the Figma annotations.

Actual: The sign-in widget is using an H3. This skips a heading level on the page - it jumps from H1 to H3. The incorrect heading level does not convey the intended structure of the content.

Screenshots

The unauthenticated experience in Staging:

The sign-in widget is using an H3. This skips a heading level on the page - it jumps from H1 to H3. The Widget header should be an H2.

The authenticated experience in Staging:

The sign-in widget is using an H3. This skips a heading level on the page - it jumps from H1 to H3. The Widget header should be an H2 and the VSO name should be an H3.

Tasks

• Unauthenticated experience: Update the Widget header (currently an H3) to be an H2.
• Authenticated experience: Update the Widget header (currently an H3) to be an H2.
• Authenticated experience: Update the representative name in the Widget (currently an H4) to be an H3.