fix(reflect): additional type predicates for isXyzType methods

[mrgrain]

This helps downstream consumers to not have to add type annotations themselves when using these methods.

Before:

function needsInterface(type: reflect.InterfaceType) {}

if (type.isInterfaceType()) {
  needsInterface(type as reflect.InterfaceType);
}

After:

function needsInterface(type: reflect.InterfaceType) {}

if (type.isInterfaceType()) {
  needsInterface(type);
}

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[mergify]

Thank you for contributing! ❤️ I will now look into making sure the PR is up-to-date, then proceed to try and merge it!

[mergify]

Merging (with squash)...