docs: Remove License trove classifer as using SPDX project license

Author: matthewfeickert

pyproject.toml

@@ -10,7 +10,7 @@ name = "pyhf"
 dynamic = ["version"]
 description = "pure-Python HistFactory implementation with tensors and autodiff"
 readme = "README.rst"
-license = { text = "Apache-2.0" }  # SPDX short identifier
+license = "Apache-2.0"
 requires-python = ">=3.8"
 authors = [
     { name = "Lukas Heinrich", email = "[email protected]" },
@@ -29,7 +29,6 @@ classifiers = [
     "Development Status :: 4 - Beta",
     "Environment :: WebAssembly :: Emscripten",
     "Intended Audience :: Science/Research",
-    "License :: OSI Approved :: Apache Software License",
     "Operating System :: OS Independent",
     "Programming Language :: Python :: 3",
     "Programming Language :: Python :: 3 :: Only",