Remove hcl2 python dependency (#3836)

* Migrate organization policy tests to standard tftest.yaml.

Remove python-hcl2 dependency and the custom python test file.
Consolidate the boolean, list, and custom constraint tests into a single `org_policies` test with a factory equivalent.
Restructure factory files into a unified `factory/` directory.

* Migrate project and folder org policy tests to standard tftest.yaml.

Replicate the organization module changes for project and folder modules:
- Remove python-hcl2 dependency usages and conftest.py.
- Remove custom python test files for org policies.
- Consolidate org policy tests into a single `org_policies` test with a factory equivalent.
- Unify factory files into a `factory/` directory.
- Remove redundant common.tfvars in folder module.

* Add factory policies directory to duplicate-diff checks.

Ensure the YAML factory files for org policies remain perfectly identical across the organization, folder, and project modules.

* Remove unused deepdiff dependency from requirements and pre-commit config.

* Add boilerplate

* fix broken link

CONTRIBUTING.md

@@ -1331,7 +1331,7 @@ def test_name(plan_summary, tfvars_to_yaml, tmp_path):
   assert s.values[address]['project'] == 'my-project'
 ```
 
-For more examples on how to write python tests, check the tests for the [`organization`](./tests/modules/organization/test_plan_org_policies.py) module.
+For more examples on how to write python tests, check the tests for the [`organization`](./tests/modules/organization/) module.
 
 ### Running tests from a temporary directory