Although I don't plan to bring over new assertions wholesale
into the current qualification branch, it's entirely possible
that various minor changes in main will use the new assertions;
having this basic support in the release branch will simplify that.
(This is why I'm adding the includes as a separate pass from
rewriting the individual assertions)
We previously asserted that for a call the function type had the same number of parameters as the declaration. But that’s not true for parameter packs anymore because the parameter pack will be exploded in the function type to account for passing multiple arguments to the pack.
To fix this, use `ConcreteDeclRef` instead of a `ValueDecl`, which has a substitution map and is able to account for the exploded parameter packs when accessed using `getParameterAt`.
rdar://100066716