Update `grape` gem to version 1.7.0

What does this MR do and why?

Contributes to #395809 (closed)

It adds Rails 7 support and other fixes: https://github.com/ruby-grape/grape/compare/v1.5.2...v1.7.0

Upgrade notes: https://github.com/ruby-grape/grape/blob/master/UPGRADING.md

I've updated majority of affected tests in separate MRs:

• Update Users API (!121700 - merged)
• Update Releases API for Grape 1.7 compatibility (!121705 - merged)
• Update Epics API for Grape 1.7 compatibility (!122061 - merged)

I did some manual testing but I mostly rely on our tests to ensure the it works.

Testing

1. Visit any API endpoint, like http://127.0.0.1:3000/api/v4/projects/2
2. It should function as usual.

MR acceptance checklist

This checklist encourages us to confirm any changes have been analyzed to reduce risks in quality, performance, reliability, security, and maintainability.

• I have evaluated the MR acceptance checklist for this MR.