Update search routes for programming expressions, vocab and resources

[dmcavoy]

I really liked the way Dave set up the route for searching for standards so I thought it would be good to move everything over to the same set up. It had the added benefit of it makes the routes file cleaner :)

Testing story

There are existing tests for these routes. I also went to the lesson edit page and tried each one manually.

PR Checklist:

• Tests provide adequate coverage
• Privacy and Security impacts have been assessed
• Code is well-commented
• New features are translatable or updates will not break translations
• Relevant documentation has been added or updated
• User impact is well-understood and desirable
• Pull Request is labeled appropriately
• Follow-up work items (including potential tech debt) are tracked and linked

[bethanyaconnor]

Thanks for doing this!

[davidsbailey]

looks great, thanks for doing this! definitely easier to make this kind of change before launch than after :-)