This should also be done for test files, but that has lower priority.

Doing this removes `<map>` from the include set of the base reporter
interface, and thus from bunch more TUs. This provides about 1.5%
improvements in the debug build of the static library, and 1% in
release build.

* Added some missing `noexcept`s on custom destructors.
* Fixed `std::move` being called on a const-reference.
* Initialized `ScopedMessage::m_moved` in class definition, instead
of doing so in constructors explicitly.
* Turned some `enum`s into `enum class`es.
* Initialized `StreamingReporterBase::currentTestCaseInfo` in class
definition.
* Some cleanups in SelfTest code.

As the full `Config` is not needed, the TUs implementing the `list*`
functions can require the less heavy header `catch_interfaces_config.hpp`
instead of the much heavier `catch_config.hpp`.

This commit also fixes up some other TUs that include `Config`,
while using just `IConfig`, to cleanup the includes further.

This is not nearly all of them, because IWYU does not support the
way Catch2 manages includes -- it expects that non-system includes
are done using `#include "foo/bar/baz.hpp"`, while Catch2 uses
`<foo/bar/baz.hpp>`. This causes trouble, because IWYU suggests
removing every single internal header, and then adding them again,
but using `""` in the include directive... the resulting suggestions
cannot be used without a lot of manual work, as they are largely
bogus.

For bonus points, IWYU also _loves_ to suggest kinda-random stdlib
headers for `size_t` and similar. Still, the resulting inclusion
graph is somewhat better than it was before.