Make httpx a dev dependency

Author: chriso

pyproject.toml

@@ -15,7 +15,6 @@ dependencies = [
     "grpc-stubs >= 1.53.0.5",
     "http-message-signatures >= 0.4.4",
     "tblib >= 3.0.0",
-    "httpx >= 0.27.0",
     "typing_extensions >= 4.10"
 ]
 
@@ -24,6 +23,7 @@ fastapi = ["fastapi", "httpx"]
 lambda = ["awslambdaric"]
 
 dev = [
+    "httpx >= 0.27.0",
     "black >= 24.1.0",
     "isort >= 5.13.2",
     "mypy >= 1.10.0",