Resources extension: TemporaryDirectory: Create a @SharedTempDir shorthand

[jbduncan]

At time of writing, we have a @Dir annotation (might be renamed to @TempDir soon) that allows temporary directories to be created in tests with minimal code.

We should consider having an equivalent for "shared" temporary directories. It should probably be named @SharedTempDir, but this is open to discussion.

Like #648, this would require a change in how ResourceExtension works, to allow annotations with an arguments field and which are indirectly/meta-annotated with @Shared(factory = TemporaryDirectory.class) to have their arguments read by the extension.

This issue is a follow-up to #348 | #491.