refactor(agent, forge): Move tests from `autogpt` to `forge` (#7247)

- Move `autogpt/tests/vcr_cassettes` submodule to `forge/tests/vcr_cassettes`
- Remove not needed markers from `pyproject.toml`: `"requires_openai_api_key", "requires_huggingface_api_key"`
- Update relevant GitHub workflows

Moved relevant tests from `autogpt/tests` to appropiate directories:
- Component tests to their respective component dirs
- `autogpt/tests/unit/test_web_search.py` → `forge/components/web/test_search.py`
- `autogpt/tests/unit/test_git_commands.py` → `forge/components/git_operations/test_git_operations.py`
- `autogpt/tests/unit/test_file_operations.py` → `forge/components/file_manager/test_file_manager.py`
- `autogpt/tests/integration/test_image_gen.py` → `forge/components/image_gen/test_image_gen.py`
- `autogpt/tests/integration/test_web_selenium.py` → `forge/components/web/test_selenium.py`
- `autogpt/tests/integration/test_execute_code.py` → `forge/components/code_executor/test_code_executor.py`
- `autogpt/tests/unit/test_s3_file_storage.py` → `forge/file_storage/test_s3_file_storage.py`
- `autogpt/tests/unit/test_gcs_file_storage.py` → `forge/file_storage/test_gcs_file_storage.py`
- `autogpt/tests/unit/test_local_file_storage.py` → `forge/file_storage/test_local_file_storage.py`
- `autogpt/tests/unit/test_json.py` → `forge/json/test_parsing.py`
- `autogpt/tests/unit/test_logs.py` → `forge/logging/test_utils.py`
- `autogpt/tests/unit/test_url_validation.py` → `forge/utils/test_url_validator.py`
- `autogpt/tests/unit/test_text_file_parsers.py` → `forge/utils/test_file_operations.py`

- (Re)moved dependencies from `autogpt/pyproject.toml` that were only used in these test files.

Also:
- Added `load_env_vars` fixture to `forge/conftest.py`
- Fixed a type error in `forge/components/web/test_search.py`
- Merged `autogpt/.gitattributes` into root `.gitattributes`

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Co-authored-by: Reinier van der Leer <[email protected]>