ci: Remove brew install libpq for macos-14 stack build

When macos-14 was rolled out libpq was not installed, but by now it is
by default. Thus, we don't need to do that, it only creates a warning
annotation right now.

.github/workflows/build.yaml

@@ -102,7 +102,6 @@ jobs:
               ~/.stack/snapshots
               ~/.stack/stack.sqlite3
             artifact: postgrest-macos-aarch64
-            deps: brew install libpq && brew link --force libpq
 
           - name: Windows
             runs-on: windows-2022