test_marketplace_json_content still expects the bmad- prefix that f44073d4 removed

[LizunovSergey]

Describe the bug
skills/bmad-module-builder/scripts/tests/test-scaffold-standalone-module.py::test_marketplace_json_content asserts marketplace["name"] == "bmad-exc" and plugin["name"] == "bmad-exc". Since f44073d ("Reserve bmad- prefix for official BMad creations only"), scaffold-standalone-module.py writes "name": args.module_code for both, so the scaffold produces exc and the test fails on main. The test was written before that change (de23928) and was not updated.

Steps to reproduce

1. cd skills/bmad-module-builder/scripts
2. uv run --no-project --with pytest --with pyyaml python -m pytest tests/test-scaffold-standalone-module.py -k marketplace

>       assert marketplace["name"] == "bmad-exc"
E       AssertionError: assert 'exc' == 'bmad-exc'
1 failed, 1 passed, 7 deselected

Expected behavior
The test matches the scaffold's current naming: both assertions expect exc (the module code without the reserved prefix).

Environment (if relevant)

• BMad Builder: main at d4a921c (2.2.2)
• Python 3.14, pytest 8, macOS