fix tests running in pypy3.10 environments

[willkg]

I made a change and it failed in all the pypy 3.10 environments with this:

Building wheels for collected packages: bleach, MarkupSafe, nh3
  Building editable for bleach (pyproject.toml): started
  Building editable for bleach (pyproject.toml): finished with status 'done'
  Created wheel for bleach: filename=bleach-6.3.0-0.editable-py3-none-any.whl size=14183 sha256=4356560a2597bee1962b9702ae0efa1729b8dc83c9e6c62bf1da2dd8b1b849d2
  Stored in directory: /private/var/folders/p6/nlmq3k8146990kpkxl73mq340000gn/T/pip-ephem-wheel-cache-zftcgcm1/wheels/a2/3c/9c/18849749afe5159a4a9c4744996318b575a197e79cfdc67971
  Building wheel for MarkupSafe (pyproject.toml): started
  Building wheel for MarkupSafe (pyproject.toml): finished with status 'done'
  Created wheel for MarkupSafe: filename=markupsafe-3.0.3-py3-none-any.whl size=8819 sha256=4511dfed160a5341d420b67df4323bab2a2e0d297700b371d71e39c0a495c56d
  Stored in directory: /Users/runner/Library/Caches/pip/wheels/aa/d6/a2/b169d01379771865d49baf7eed18e85b0a0214fc493278d0d1
  Building wheel for nh3 (pyproject.toml): started
  Building wheel for nh3 (pyproject.toml): finished with status 'error'
  error: subprocess-exited-with-error
  
  × Building wheel for nh3 (pyproject.toml) did not run successfully.
  │ exit code: 1
  ╰─> [100 lines of output]
      Running `maturin pep517 build-wheel -i /Users/runner/hostedtoolcache/PyPy/3.10.16/arm64/bin/python --compatibility off`
      📦 Including license file `LICENSE`
      🔗 Found pyo3 bindings with abi3 support
      🐍 Found PyPy 3.10 at /Users/runner/hostedtoolcache/PyPy/3.10.16/arm64/bin/python
Successfully built bleach MarkupSafe
      📡 Using build options features from pyproject.toml
Failed to build nh3
      ⚠️ Warning: PyPy 3.10 at /Users/runner/hostedtoolcache/PyPy/3.10.16/arm64/bin/python does not yet support abi3 so the build artifacts will be version-specific.
      💻 Using `MACOSX_DEPLOYMENT_TARGET=11.0` for aarch64-apple-darwin by default
         Compiling proc-macro2 v1.0.103
...
         Compiling autocfg v1.5.0
      error: failed to run custom build command for `pyo3-ffi v0.27.1`
      
      Caused by:
        process didn't exit successfully: `/private/var/folders/p6/nlmq3k8146990kpkxl73mq340000gn/T/pip-install-7v9mr5rb/nh3_2191fb777c5c4b7cb148079d27ef72fd/target/release/build/pyo3-ffi-afc081597c3be684/build-script-build` (exit status: 1)
        --- stdout
        cargo:rustc-check-cfg=cfg(Py_LIMITED_API)
        cargo:rustc-check-cfg=cfg(Py_GIL_DISABLED)
        cargo:rustc-check-cfg=cfg(PyPy)
        cargo:rustc-check-cfg=cfg(GraalPy)
        cargo:rustc-check-cfg=cfg(py_sys_config, values("Py_DEBUG", "Py_REF_DEBUG", "Py_TRACE_REFS", "COUNT_ALLOCS"))
        cargo:rustc-check-cfg=cfg(pyo3_disable_reference_pool)
        cargo:rustc-check-cfg=cfg(pyo3_leak_on_drop_without_reference_pool)
        cargo:rustc-check-cfg=cfg(Py_3_7)
        cargo:rustc-check-cfg=cfg(Py_3_8)
        cargo:rustc-check-cfg=cfg(Py_3_9)
        cargo:rustc-check-cfg=cfg(Py_3_10)
        cargo:rustc-check-cfg=cfg(Py_3_11)
        cargo:rustc-check-cfg=cfg(Py_3_12)
        cargo:rustc-check-cfg=cfg(Py_3_13)
        cargo:rustc-check-cfg=cfg(Py_3_14)
        cargo:rustc-check-cfg=cfg(Py_3_15)
        cargo:rerun-if-env-changed=PYO3_CROSS
        cargo:rerun-if-env-changed=PYO3_CROSS_LIB_DIR
        cargo:rerun-if-env-changed=PYO3_CROSS_PYTHON_VERSION
        cargo:rerun-if-env-changed=PYO3_CROSS_PYTHON_IMPLEMENTATION
        cargo:rerun-if-env-changed=PYO3_PRINT_CONFIG
      
        --- stderr
        error: the configured PyPy interpreter version (3.10) is lower than PyO3's minimum supported version (3.11)
      warning: build failed, waiting for other jobs to finish...
      💥 maturin failed
        Caused by: Failed to build a native library through cargo
        Caused by: Cargo build finished with "exit status: 101": `env -u CARGO MACOSX_DEPLOYMENT_TARGET="11.0" PYO3_BUILD_EXTENSION_MODULE="1" PYO3_ENVIRONMENT_SIGNATURE="pypy-3.10-64bit" PYO3_PYTHON="/Users/runner/hostedtoolcache/PyPy/3.10.16/arm64/bin/python" PYTHON_SYS_EXECUTABLE="/Users/runner/hostedtoolcache/PyPy/3.10.16/arm64/bin/python" "cargo" "rustc" "--profile" "release" "--features" "pyo3/extension-module" "--message-format" "json-render-diagnostics" "--manifest-path" "/private/var/folders/p6/nlmq3k8146990kpkxl73mq340000gn/T/pip-install-7v9mr5rb/nh3_2191fb777c5c4b7cb148079d27ef72fd/Cargo.toml" "--lib" "--" "-C" "link-arg=-undefined" "-C" "link-arg=dynamic_lookup" "-C" "link-args=-Wl,-install_name,@rpath/nh3.abi3.so"`
      Error: command ['maturin', 'pep517', 'build-wheel', '-i', '/Users/runner/hostedtoolcache/PyPy/3.10.16/arm64/bin/python', '--compatibility', 'off'] returned non-zero exit status 1
      [end of output]
  
  note: This error originates from a subprocess, and is likely not a problem with pip.
  ERROR: Failed building wheel for nh3
error: failed-wheel-build-for-install

× Failed to build installable wheels for some pyproject.toml based projects
╰─> nh3
Error: Process completed with exit code 1.

https://pypy.org/posts/2025/07/pypy-v7320-release.html suggests maybe pypy 3.10 is unsupported and we have to update to pypy 3.11.