update license specification

Author: pvsr

pyproject.toml

@@ -2,14 +2,14 @@
 name = "qbpm"
 version = "1.0-rc2"
 description = "qutebrowser profile manager"
-license = { file = "LICENSE" }
+license = "GPL-3.0-or-later"
+license-files = ["LICENSE"]
 readme = "README.md"
 authors = [{ name = "Peter Rice", email = "[email protected]" }]
 classifiers = [
     "Development Status :: 4 - Beta",
     "Environment :: Console",
     "Intended Audience :: End Users/Desktop",
-    "License :: OSI Approved :: GNU General Public License v3 or later (GPLv3+)",
     "Operating System :: MacOS",
     "Operating System :: POSIX :: Linux",
     "Programming Language :: Python :: 3",