Tighten search page error handling

If a user sends `page[]=1` as a param, we'll get a Vector here, which
will cause a ClassCastException instead of a NumberFormatException. So
we'll just catch any exception here and return an error response instead
of triggering a 500.

src/clojars/web.clj

@@ -38,7 +38,7 @@
   [maybe-page]
   (try
     (Integer/parseInt maybe-page)
-    (catch NumberFormatException _nfe
+    (catch Exception _
       (throw (ex-info
               "page must be an integer"
               {:report? false