update return type for AuthCheck and SuspenseWithPerf to JSX.Element

[seanemmer]

Update return type from React.ReactNode to JSX.Element

Resolves #138

[seanemmer]

This passes the test suite locally - looks like 'yarn build' is failing in the CI pipeline.

[jhuleatt]

yarn build runs the TypeScript compiler, and it looks like it is failing on a type error caused by the switch to JSX.Element:

auth/index.tsx:85:5 - error TS2322: Type 'ReactNode' is not assignable to type 'Element'.
  Type 'string' is not assignable to type 'Element'.
85     return fallback;
       ~~~~~~~~~~~~~~~~
auth/index.tsx:87:5 - error TS2322: Type 'ReactNode' is not assignable to type 'Element'.
  Type 'string' is not assignable to type 'Element'.
87     return children;
       ~~~~~~~~~~~~~~~~
Found 2 errors.
error Command failed with exit code 2.

I also got this error when running yarn build locally. I'll add some comments in the review that explain how to fix it.

[jhuleatt]

This and the change on line 36 cause a typescript compile error because they conflict with the props declared on line 47 and 48

[jhuleatt]

After playing around with the PR branch for a bit, I think this confirms that switching to JSX.Element is not the right way to go. I'm still getting warnings when I try to use a string as a child/fallback:

[seanemmer]

I wrapped the child/fallback in a React fragment to handle the string scenario - this is similar to what was already done for PerfCheck

[jhuleatt]

Thank you @seanemmer! Looks like it is working now 🔥