Skip testing PyPy wheels

One of the test builds on #15015 failed to install a pp38-* wheel
because it didn't have access to the openssl headers to build
`cryptography` from source. We don't run CI against PyPy so I'm going to
be a meanie and skip testing the wheels. (And I've no idea why 3.8 was
special in the first place, either.)

.github/workflows/release-artifacts.yml

@@ -148,7 +148,7 @@ jobs:
         env:
           # Skip testing for platforms which various libraries don't have wheels
           # for, and so need extra build deps.
-          CIBW_TEST_SKIP: pp3{7,9}-* *i686* *musl*
+          CIBW_TEST_SKIP: pp3*-* *i686* *musl*
           # Fix Rust OOM errors on emulated aarch64: https://github.com/rust-lang/cargo/issues/10583
           CARGO_NET_GIT_FETCH_WITH_CLI: true
           CIBW_ENVIRONMENT_PASS_LINUX: CARGO_NET_GIT_FETCH_WITH_CLI