Remove license classifier incompatible with setuptools PEP 639

setuptools rejects License classifiers when license expression is set.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Author: dcj

pyproject.toml

@@ -16,7 +16,6 @@ keywords = ["mqtt", "homie", "iot", "ebus"]
 classifiers = [
     "Development Status :: 3 - Alpha",
     "Intended Audience :: Developers",
-    "License :: OSI Approved :: MIT License",
     "Programming Language :: Python :: 3",
     "Programming Language :: Python :: 3.10",
     "Programming Language :: Python :: 3.11",