pyproject.toml: drop Python 3.8 support

Signed-off-by: Bastian Krause <bst@pengutronix.de>

Author: Bastian-Krause

pyproject.toml

@@ -16,15 +16,14 @@ authors = [
 description = "embedded systems control library for development, testing and installation"
 readme = "README.rst"
 license = { file="LICENSE" }
-requires-python = ">=3.8"
+requires-python = ">=3.9"
 classifiers = [
     "Intended Audience :: Developers",
     "Development Status :: 5 - Production/Stable",
     "Operating System :: POSIX :: Linux",
     "Topic :: Software Development :: Testing",
     "Framework :: Pytest",
     "Programming Language :: Python :: 3 :: Only",
-    "Programming Language :: Python :: 3.8",
     "Programming Language :: Python :: 3.9",
     "Programming Language :: Python :: 3.10",
     "Programming Language :: Python :: 3.11",
@@ -228,7 +227,7 @@ signature-mutators = ["labgrid.step.step"]
 [tool.tox]
 legacy_tox_ini = """
 [tox]
-envlist = py38, py39, py310, py311, py312
+envlist = py39, py310, py311, py312
 isolated_build = true
 
 [testenv]