swtich to 3.8 again because 3.9.7 has problem here: python-websockets…

…/websockets#1051

.devcontainer/devcontainer.json

@@ -7,7 +7,7 @@
 			// Update 'VARIANT' to pick a Python version: 3, 3.9, 3.8, 3.7, 3.6.
 			// Append -bullseye or -buster to pin to an OS version.
 			// Use the -bullseye variants if you are on a M1 mac.
-			"VARIANT": "3.9",
+			"VARIANT": "3.8",
 			// Options
 			"NODE_VERSION": "lts/*"
 		}