raco exe: fix --collects-dest for non-default "compiled"

pkgs/compiler-test/tests/compiler/embed/test.rkt

@@ -750,8 +750,9 @@
 
 (try-basic)
 (try-mzc)
-(unless (eq? 'windows (system-type))
-  (try-extension))
+(when (eq? 'racket (system-type 'vm))
+  (unless (eq? 'windows (system-type))
+    (try-extension)))
 (try-gracket)
 (try-reader)
 (try-lang)

racket/collects/compiler/embed.rkt

@@ -405,7 +405,10 @@
                   (extract-last (unix-style-split s)))])
     (let ([p (build-path collects-dest
                          (apply build-path dir)
-                         "compiled"
+                         (let ([l (use-compiled-file-paths)])
+                           (if (pair? l)
+                               (car l)
+                               "compiled"))
                          (path-add-extension file #".zo"))])
       (let-values ([(base name dir?) (split-path p)])
         (make-directory* base)