Feature/xss escaping modules

[joeyblake]

Types of change

• Bug fix (change which fixes an issue)
• Enhancement (change which improves upon an existing feature)
• New feature (change which adds new functionality)

Description

Adds context specific late escaping filters to improve XSS security. This ensures that escaping does not interfere with other logic use cases, in the code it is clear that the string is escaped at output, and any changes further up in the logic will not open up the same vulnerabilities in the future.

https://developers.hubspot.com/docs/cms/hubl/filters#escape-html
https://developers.hubspot.com/docs/cms/hubl/filters#escape-attr
https://developers.hubspot.com/docs/cms/hubl/filters#escape-url
https://developers.hubspot.com/docs/cms/hubl/filters#escape-js
https://developers.hubspot.com/docs/cms/hubl/filters#sanitize-html

Relevant links

Example page:
GitHub issue:

Checklist

• I have read the CONTRIBUTING document.
• My code follows the style guide requirements.
• I have thoroughly tested my change.

People to notify

[jasonnrosa]

Looking good to me! Just one comment on one of the variables used for menu depth