Add test coverage for public API surface of MouseActionConverter

[h3xds1nz]

Description

Adds test coverage for MouseActionConverter. I've also fixed an unintentional behavioral change I've introduced with #9676, which would mean it wouldn't throw InvalidEnumArgumentException due to passing wrong value type to the exception.

• As I've outlined previously, there are basically two (in my opinion) bugs in the class
  • CanConvertTo throws InvalidCastException due to an unboxing cast when you pass an int
  • The same thing happens in ConvertTo when you pass an int within range

Customer Impact

Improved test coverage on public surface.

Regression

Fixing my own oversight at the same time.

Testing

Local build.

Risk

Low.

Microsoft Reviewers: Open in CodeFlow

[dipeshmsft]

As I've outlined previously, there are basically two (in my opinion) bugs in the class

• CanConvertTo throws InvalidCastException due to a cast when you pass an int
• The same thing happens in ConvertTo when you pass an int within range

Good point, this looks like an issue in the class implementation.

[dipeshmsft]

Rest of the changes look good to me.

[h3xds1nz]

@dipeshmsft Added a bit more cases as well and converted to file-scoped as with all my newer tests (will do that bit for TextDecorations as well). It's rebased btw so I had to force push.