Update Android test-command handling (#2590)

* Update Android test-command handling

* Update to Python 3.13.8

* Update documentation and tests

* Deal with `sysconfig.get_config_var("exec_prefix")` changing in Python 3.14, and add cross venv tests

* Allow test commands starting with `python3`

* test-command cleanups

* [pre-commit.ci] auto fixes from pre-commit.com hooks

for more information, see https://pre-commit.ci

---------

Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>

cibuildwheel/platforms/android.py

@@ -617,8 +617,11 @@ def test_wheel(state: BuildState, wheel: Path) -> None:
 
     # Parse test-command.
     test_args = shlex.split(test_command)
-    if test_args[:2] in [["python", "-c"], ["python", "-m"]]:
-        test_args[:3] = [test_args[1], test_args[2], "--"]
+    if test_args[0] in ["python", "python3"] and any(arg in test_args for arg in ["-c", "-m"]):
+        # Forward the args to the CPython testbed script. We require '-c' or '-m'
+        # to be in the command, because without those flags, the testbed script
+        # will prepend '-m test', which will run Python's own test suite.
+        del test_args[0]
     elif test_args[0] in ["pytest"]:
         # We transform some commands into the `python -m` form, but this is deprecated.
         msg = (
@@ -627,11 +630,11 @@ def test_wheel(state: BuildState, wheel: Path) -> None:
             "If this works, all you need to do is add that to your test command."
         )
         log.warning(msg)
-        test_args[:1] = ["-m", test_args[0], "--"]
+        test_args.insert(0, "-m")
     else:
         msg = (
             f"Test command {test_command!r} is not supported on Android. "
-            f"Supported commands are 'python -m' and 'python -c'."
+            f"Command must begin with 'python' or 'python3', and contain '-m' or '-c'."
         )
         raise errors.FatalError(msg)
 
@@ -646,6 +649,7 @@ def test_wheel(state: BuildState, wheel: Path) -> None:
         "--cwd",
         cwd_dir,
         *(["-v"] if state.options.build_verbosity > 0 else []),
+        "--",
         *test_args,
         env=state.build_env,
     )