Fix Gobview by using batteries.unthreaded in goblint_parallel

Failure since #1749 (comment).
Hopefully this works.

Author: sim642

src/util/parallel/dune

@@ -4,12 +4,12 @@
  (name goblint_parallel)
  (public_name goblint.parallel)
  (libraries
-   batteries
+   batteries.unthreaded
    (select gobMutex.ml from
       (domainslib -> gobMutex.domainslib.ml)
       ( -> gobMutex.no-domainslib.ml)
    )
-   (select threadpool.ml from 
+   (select threadpool.ml from
       (domainslib -> threadpool.domainslib.ml)
       (-> threadpool.no-domainslib.ml)
    )