gh-152132: Test all PyRun functions in test_capi.test_run

[vstinner]

PyRun_InteractiveOneObjectEx() now raises TypeError if the second parameter type is not str.

• Issue: Py_RunMain incorrectly exits process on SystemExit when running commands/files #152132

[miss-islington-app]

Thanks @vstinner for the PR 🌮🎉.. I'm working now to backport this PR to: 3.13, 3.14, 3.15.
🐍🍒⛏🤖

[bedevere-app]

GH-153411 is a backport of this pull request to the 3.15 branch.

[miss-islington-app]

Sorry, @vstinner, I could not cleanly backport this to 3.13 due to a conflict.
Please backport using cherry_picker on command line.

cherry_picker cd9994e2831ea743e5423c1db56ca2ca42154e0a 3.13

[bedevere-app]

GH-153412 is a backport of this pull request to the 3.14 branch.

[vstinner]

While writing new tests, I got two bugs/crashes:

• Assertion error in _PyPegen_raise_error_known_location() when running PyRun_SimpleFileExFlags() #153304
• import _testcapi; _testcapi.run_string(b'', 0) did crash. I worked around the issue by checking the start argument in _testcapi.

TODO: The tests don't cover all code paths:

• PyRun_AnyFile*() family calls _PyRun_InteractiveLoopObject() if _Py_FdIsInteractive(fp, filename) is true. I tried but failed so far to write tests using pty.openpty() to have a TTY which can be fully controlled.
• Compiler flags are not tested.
• PyRun_SimpleFile*() family: the .pyc code path is not tested.