Test case to document behaviour of Record x Single-value Constructor x JsonValue annotation, for #3180

[yihtserns]

After I provided update to #3180, I suddenly remembered documentating an observation that Record with 1-arg constructor will produce Properties-based Creator when I was working on #3724, so this shouldn't have worked:

record Watts(@JsonValue double value) {
}

mapper.readValue("123", Watts.class);

But it turns out that:

1. Record with 1-arg header/constructor:
   • Properties-based creator
2. Record with N-args header/constructor + 1-arg (alternative/custom) constructor:
   • Properties-based creator (for the canonical constructor)
   • Delegating creator (for the alternative/custom constructor)
3. Record with 1-arg header/constructor + @JsonValue:
   • Delegating creator

This PR is to add test cases to document (and to catch potential future regression) number 3.

UPDATE: Just found out behaviour number 3 came from #3654. Nice. 👍

[cowtowncoder]

Ok, rules do get quite complicated. But I agree, better to have tests covering them & working as documentation.