Restore single pass over form children

This reverts to a scenario where parse-all does only a single pass over
the children nodes.

It does this by replacing a `doall` + `last` with just `last`. The
`last` is new code as of the prior commit, so this switches back to a
single pass over the children. It's not clear what the `doall` was
doing. Perhaps it ensured that a file was fully parsed before closing,
though I tried and failed to confirm that. In any case, the `last`
should serve the same purpose.

Author: mainej

src/rewrite_clj/parser.cljc

@@ -23,12 +23,11 @@
   "Parse all forms from the given reader."
   [#?(:cljs ^not-native reader :default reader)]
   (let [nodes (->> (repeatedly #(parse reader))
-                   (take-while identity)
-                   (doall))]
-    (with-meta
-      (nforms/forms-node nodes)
-      (merge (meta (first nodes))
-             (select-keys (meta (last nodes)) [:end-row :end-col])))))
+                   (take-while identity))
+        position-meta (merge (meta (first nodes))
+                             (select-keys (meta (last nodes))
+                                          [:end-row :end-col]))]
+    (with-meta (nforms/forms-node nodes) position-meta)))
 
 ;; ## Specialized Parsers