editors/vscode: Fix pkg-plist

The string "311" has been inadvertently substituted with
%%PYTHON_SUFFIX%% by make makeplist.

That has caused an error in the package phase for users using
non-default python versions (e.g. 3.12).

PR: 294660
Reported by: Dean E. Weimer <dweimer@dweimer.net>
Tested by: Dean E. Weimer <dweimer@dweimer.net>