Vote-2349: Add "On this page" transltion for spanish

[clmedders]

Jira ticket

Vote-2349

Description

Adding the Spanish translation for "On this page" for the in-page nav.

Deployment and testing

Post-deploy steps

1. run lando retune

QA/Testing instructions

1. log in as an admin locally and visit http://vote-gov.lndo.site/node/82/translations and add a spanish translation (just save the page no need to worry about other text).
2. verify that On this page has been translated.

Checklist for the Developer

• A link to the JIRA ticket has been included above.
• No merge conflicts exist with the target branch.
• Automated tests have passed on this PR.
• A reviewer has been designated.
• Deployment and testing steps have been documented above, if applicable.

Checklist for the Peer Reviewers

• The file changes are relevant to the task objective.
• Code is readable and includes appropriate commenting.
• Code standards and best practices are followed.
• QA/Test steps were successfully completed, if applicable.
• Applicable logs are free of errors.