Remove SuppressCompositePrimaryKeyWarning concern

Ref: #292909 (closed)

What does this MR do and why?

This MR removes SuppressCompositePrimaryKeyWarning concern as we can explicitly set the primary key in the model directly instead to silent this warning.

➜  gitlab git:(432604-fix-project-builder-cross-joins) ✗ bundle exec rspec --color spec/models/project_authorization_spec.rb
Run options: include {:focus=>true}

All examples were filtered out; ignoring {:focus=>true}

Test environment set up in 3.35989 seconds
.................

Finished in 9.81 seconds (files took 13.9 seconds to load)
17 examples, 0 failures

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