insert examples directly into drracket instead of simulating

typing them in, in the module language test suite

this speeds it up; going from 140 to 105 seconds on my (mac)
machine. (drdr was taking 240 or so seconds, tho)

collects/tests/drracket/private/module-lang-test-utils.rkt

@@ -89,7 +89,7 @@
                    (or (test-interactions test) 'no-interactions)
                    after-execute-output)
           (k (void)))
-        (type-in-interactions drs ints)
+        (insert-in-interactions drs ints)
         ;; set to be the paragraph right after the insertion.
         (set! output-start-paragraph
               (queue-callback/res