Add a test for property access on ~Escapable types

[natecook1000]

This tests using a ~Escapable type as the LHS of a property access inside the #expect and #require macros. A ~Escapable return value from #require is unsupported.

Checklist:

• [x] Code and documentation should follow the style of the Style Guide.
• [x] If public symbols are renamed or modified, DocC references should be updated.

[stmontgomery]

@swift-ci please test

[grynspan]

I believe this test is dependent on #840, right?

[natecook1000]

Right! I believe it's aimed at that branch, not main. Should I direct it somewhere else?

[grynspan]

Nope, just confirming the dependency is why the test failed. You could redirect the PR to merge to that branch, and then it would pass?

[grynspan]

@swift-ci test