Release 3198

validate for a location or query
small rubocop fixes on other files

Trello card

Surface a validation error

Context

The Schools Experience does not show an error if the location field is left blank when searching for a schools experience

This is a re-implementation of work originally done in PR #3159 - now using Rails validators and GOVUK frontend libraries

Changes proposed in this pull request

Validate for location

Guidance to review