updated _apply_configuration() to redact tmux_conf_ variables from environment in a single call

.tmux.conf

@@ -1216,7 +1216,8 @@ run -b '[ -z "#{window_active}" ] && [ -z "#{version}" ] && tmux set display-tim
 #   _apply_overrides
 #   _apply_bindings
 #   _apply_theme
-#   for name in $(printenv | grep -E -o '^tmux_conf_[^=]+'); do tmux setenv -gu "$name"; done;
+#   # shellcheck disable=SC2046
+#   tmux setenv -gu tmux_conf_dummy $(printenv | grep -E -o '^tmux_conf_[^=]+' | awk '{printf "; setenv -gu %s", $0}')
 # }
 #
 # _urlview() {