test(ci[move]): Relocate test_package_tools.py to tests/ci/

why: Keep CI-tooling tests colocated with test_bump_version.py under a
single tests/ci/ subpackage that mirrors scripts/ci/.
what:
- git mv tests/test_package_tools.py tests/ci/test_package_tools.py
- Adjust sys.path insertion depth (parents[1] -> parents[2]).

Author: tony

tests/test_package_tools.py tests/ci/test_package_tools.pytests/test_package_tools.py renamed to tests/ci/test_package_tools.py

@@ -7,7 +7,7 @@
 
 import pytest
 
-sys.path.insert(0, str(pathlib.Path(__file__).resolve().parents[1] / "scripts" / "ci"))
+sys.path.insert(0, str(pathlib.Path(__file__).resolve().parents[2] / "scripts" / "ci"))
 import package_tools