Update index.html.md.erb Changed Append to Prepend

Misused term (or terms)

• Append

Alternatives

• Prepend

Reason why

The document was inconsistent. It said to "Append" when the example showed it prepending.

Author checklist

I am not sure this is the correct template for what I am fixing.

• Named the MR appropriately
• Updated data/communication/misused_terms.yml properly
• Reviewed how it renders on the Top Misused Terms page
• Submit for review

Review process

• Assign to any GitLab team member for initial review and approval.
• Assign to the Diversity and Inclusion Manager (@cwilliams3) for final review and merge.