gh-133742: Fix test_sysconfig and test_build_details for relocated directories

[pablogsal]

• Issue: test_sysconfig fails if executed from a relocated place #133742

[pablogsal]

Before:

   'py_version_short': '3.15',
-  'srcdir': '/home/pablogsal/github/python/main/ins2/lib/python3.15/config-3.15d-x86_64-linux-gnu'}
?                                                   -

+  'srcdir': '/home/pablogsal/github/python/main/ins/lib/python3.15/config-3.15d-x86_64-linux-gnu'}

0:00:00 load avg: 2.40 [1/2/1] test_sysconfig failed (1 failure)
0:00:00 load avg: 2.40 [2/2/1] test_build_details
======================================================================
FAIL: test_base_interpreter (test.test_build_details.CPythonBuildDetailsTests.test_base_interpreter)
----------------------------------------------------------------------
Traceback (most recent call last):
  File "/home/pablogsal/github/python/main/ins2/lib/python3.15/test/test_build_details.py", line 127, in test_base_interpreter
    self.assertEqual(os.path.realpath(value), os.path.realpath(sys.executable))
    ~~~~~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
AssertionError: '/home/pablogsal/github/python/main/ins/bin/python3.15' != '/home/pablogsal/github/python/main/ins2/bin/python3.15'
- /home/pablogsal/github/python/main/ins/bin/python3.15
+ /home/pablogsal/github/python/main/ins2/bin/python3.15
?                                       +


======================================================================
FAIL: test_c_api (test.test_build_details.CPythonBuildDetailsTests.test_c_api)
----------------------------------------------------------------------
Traceback (most recent call last):
  File "/home/pablogsal/github/python/main/ins2/lib/python3.15/test/test_build_details.py", line 137, in test_c_api
    self.assertTrue(os.path.exists(os.path.join(value['headers'], 'Python.h')))
    ~~~~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
AssertionError: False is not true0:00:00 load avg: 2.40 [2/2/2] test_build_details failed (2 failures)

== Tests result: FAILURE ==

2 tests failed:
    test_build_details test_sysconfig

Total duration: 531 ms
Total tests: run=47 failures=3 skipped=3
Total test files: run=2/2 failed=2
Result: FAILURE

After:

./ins2/bin/python3 -m test test_sysconfig test_build_details
Using random seed: 403838756
0:00:00 load avg: 2.60 Run 2 tests sequentially in a single process
0:00:00 load avg: 2.60 [1/2] test_sysconfig
0:00:00 load avg: 2.60 [1/2] test_sysconfig passed
0:00:00 load avg: 2.60 [2/2] test_build_details
0:00:00 load avg: 2.60 [2/2] test_build_details passed

== Tests result: SUCCESS ==

All 2 tests OK.

Total duration: 451 ms
Total tests: run=47 skipped=5
Total test files: run=2/2
Result: SUCCESS

[miss-islington-app]

Thanks @pablogsal for the PR 🌮🎉.. I'm working now to backport this PR to: 3.14.
🐍🍒⛏🤖 I'm not a witch! I'm not a witch!

[bedevere-app]

GH-136990 is a backport of this pull request to the 3.14 branch.