Remove facebook and rss from footer

[JPrevost]

Relevant ticket(s):

• https://mitlibraries.atlassian.net/browse/UXWS-1511

How does this address that need:

• Removes the two links

Document any side effects to this change:

• A css rule was updated to keep similar sizing when moving from 5 to 3 elements in the flexbox. The rails apps did not need this, but since they use a different grid altogether this may not be unexpected.

Developer

Secrets

• All new secrets have been added to Pantheon tiers
• Relevant secrets have been updated in Github Actions
• All new secrets documented in README

Documentation

• Project documentation has been updated
• No documentation changes are needed

Accessibility

• ANDI or Wave has been run in accordance to
  our guide and
  all issues introduced by these changes have been resolved or opened as new
  issues (link to those issues in the Pull Request details above)

Stakeholder approval

• Stakeholder approval has been confirmed
• Stakeholder approval is not needed

Dependencies

NO dependencies are updated

Code Reviewer

• The commit message is clear and follows our guidelines
  (not just this pull request message)
• The changes have been verified
• The documentation has been updated or is unnecessary
• New dependencies are appropriate or there were no changes

[matt-bernhardt]

This looks pretty straightforward. I'm still trying to wrap my head around why the CSS change is necessary, but am not going to argue that it works. I kind of hate the whole way that this "identity" div behaves, but that's not the point of this work.