Description

Currently (.NET 7 RC2) both DateTime and DateOnly are allowed as Dictionary keys, but not TimeOnly. This seems strange.

Reproduction Steps

Try returning Dictionary that has at least one item with TimeOnly as a key from an API action.

Expected behavior

Getting the serialized response

Actual behavior

Exception

Regression?

No

Known Workarounds

Creating custom convertor

Configuration

.NET 7 RC2

Other information

No response