@FetchOne improvements (#63)

* Deprecate `@FetchAll/One` parameter pack use

We maintain a ton of overloads to support them, but they are not very
ergonomic. We provide a far better tool for packing values together, and
that's the `@Selection` macro, so let's steer folks that direction.

* wip

* wip

* wip

* wip

Author: stephencelis

.github/workflows/ci.yml

@@ -33,7 +33,7 @@ jobs:
     strategy:
       matrix:
         swift:
-          - '6.0'
+          - '6.1'
     runs-on: ubuntu-latest
     container: swift:${{ matrix.swift }}
     steps: