Fix garbage on session start

Use the workaround mentioned in
https://github.com/microsoft/WSL/issues/5931 to stop garbage being
output when starting a new session.

tmux.conf

@@ -1,3 +1,6 @@
+# Address vim mode switching delay & garbage text on start
+set -s escape-time 1
+
 # Set global hooks to perform actions when events occur
 set-hook -g session-created 'run ~/.config/tmux/hooks/session-create.sh'
 
@@ -12,9 +15,6 @@ unbind C-b
 set -g prefix C-Space
 bind Space send-prefix
 
-# Address vim mode switching delay
-set -s escape-time 0
-
 # Increase scrollback buffer size
 set -g history-limit 1000000