Skip tests on Linux CI (SwiftCIFP_E2E uses Apple-only APIs)

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Author: RISCfuture

.github/workflows/ci.yml

@@ -48,8 +48,6 @@ jobs:
       - uses: actions/checkout@v4
       - name: Build
         run: swift build --target SwiftCIFP -v
-      - name: Test
-        run: swift test -v
   lint:
     name: Run Swiftlint
     runs-on: ubuntu-latest