break(framework) Drop Python 3.8 support (#4180)

pyproject.toml

@@ -30,7 +30,6 @@ classifiers = [
     "Programming Language :: Python",
     "Programming Language :: Python :: 3",
     "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",
@@ -66,7 +65,7 @@ flwr-clientapp = "flwr.client.clientapp:flwr_clientapp"
 flower-client-app = "flwr.client.supernode:run_client_app"  # Deprecated
 
 [tool.poetry.dependencies]
-python = "^3.8"
+python = "^3.9"
 # Mandatory dependencies
 numpy = "^1.21.0"
 grpcio = "^1.60.0,!=1.64.2,!=1.65.1,!=1.65.2,!=1.65.4"
@@ -79,7 +78,7 @@ tomli = "^2.0.1"
 tomli-w = "^1.0.0"
 pathspec = "^0.12.1"
 # Optional dependencies (Simulation Engine)
-ray = { version = "==2.10.0", optional = true, python = ">=3.8,<3.12" }
+ray = { version = "==2.10.0", optional = true, python = ">=3.9,<3.12" }
 # Optional dependencies (REST transport layer)
 requests = { version = "^2.31.0", optional = true }
 starlette = { version = "^0.31.0", optional = true }