disable the extra information redex puts for check syntax

... because it results in programs that have different identifiers
with overlapping ranges in the editor, something that check syntax is
not yet prepared to deal with.

collects/redex/private/rewrite-side-conditions.rkt

@@ -87,6 +87,8 @@
       (when the-use
         (define old (syntax-property void-stx 'disappeared-use))
         (set! void-stx
+              void-stx ;; disable this for now.
+              #;
               (syntax-property void-stx
                                'disappeared-use
                                (if old (cons the-use old) the-use)))))

collects/redex/private/term-fn.rkt

@@ -105,7 +105,9 @@
                             ;; shorten the span so it covers only up to the underscore
                             (string-length (symbol->string nt))))
         (define the-id (datum->syntax table-entry nt the-srcloc id-stx))
-        (syntax-property the-id 'syncheck-original #t)]
+        (syntax-property the-id 'syncheck-original #t)
+        ;; disable this for now
+        #f]
        [else
         #f])]
     [else