Cannot import @compiled/utils from within @compiled/jest source code

[dddlr]

Follow-up to #1667

We cannot import any functions defined within @compiled/utils (packages/utils/) from within @compiled/jest (packages/jest/), as the TypeScript setup (with rootDir etc) would break when running yarn build. As a result, we have an extra file packages/jest/src/utils.ts that essentially just duplicates the functions defined in packages/utils/.

This is less than ideal from a maintenance perspective - would be good to be able to de-duplicate this and use @compiled/utils directly.