Drop support for Python 3.8

pyproject.toml

@@ -12,7 +12,7 @@ name = "pytensor"
 dynamic = [
   'version'
 ]
-requires-python = ">=3.7"
+requires-python = ">=3.8"
 authors = [
     {name = "pymc-devs", email = "pymc.devs@gmail.com"}
 ]
@@ -34,7 +34,6 @@ classifiers = [
     "Operating System :: Unix",
     "Operating System :: MacOS",
     "Programming Language :: Python :: 3",
-    "Programming Language :: Python :: 3.7",
     "Programming Language :: Python :: 3.8",
     "Programming Language :: Python :: 3.9",
     "Programming Language :: Python :: 3.10",