Fix broken calling convention for `[EXPBlockDefinedMatcher matches:]`

Any `EXPBlockDefinedMatcher` effectively ignores the argument passed to `matches:` and instead fetches the `actual` from it's instance with `self.actual`. This adds mental overhead and makes @ollieatkinson 's work on enabling a syntax similar to `expect(@[ @1, @2]).elements.to.equal(1)` for collections messy.
Remove `-[EXPExpect applyMathcer:to]`

This method seems to add unnecessary complication to the calling convention and appears to only have originally existed to allow for Async testing. The `to:(NSObject **)actual` parameter in `-[EXPExpect applyMatcher:to:]` appears to only have existed for the purpose of being a flag to say “we have a value now” - this is no longer required with the fixes from the previous commit.