fix: TravisCI failures & status (pypa#1970)

* fix: TravisCI failures & status
* Allow failure on s390x

.travis.yml

@@ -44,6 +44,7 @@ jobs:
       python: 3.9
       services: docker
       arch: s390x
+      allow_failure: True
       env: PYTHON=python
 
 install:
@@ -56,5 +57,7 @@ script: |
   (while true; do echo "travis_keep_alive"; sleep 300; done) &
   SPINNER_PID=$!
   disown
-  $PYTHON ./bin/run_tests.py --num-processes 2
+  result=0
+  $PYTHON ./bin/run_tests.py --num-processes 2 || result=1
   kill -9 ${SPINNER_PID}
+  test ${result} -eq 0

test/test_emscripten.py

@@ -6,7 +6,7 @@
 
 import pytest
 
-from cibuildwheel.util import CIBW_CACHE_PATH
+from cibuildwheel.util import CIBW_CACHE_PATH, CIProvider, detect_ci_provider
 
 from . import test_projects, utils
 
@@ -49,6 +49,9 @@ def test_pyodide_build(tmp_path, use_pyproject_toml):
     if not shutil.which("python3.12"):
         pytest.skip("Python 3.12 not installed")
 
+    if detect_ci_provider() == CIProvider.travis_ci:
+        pytest.skip("Python 3.12 is just a non-working pyenv shim")
+
     if use_pyproject_toml:
         basic_project.files["pyproject.toml"] = textwrap.dedent(
             """