Fix for the procedure remove in chaining maps

Author: jvdp1

src/stdlib_hashmap_chaining.f90

@@ -775,6 +775,7 @@ module subroutine remove_chaining_entry(map, key, existed)
         centry % next => bentry
         map % inverse(inmap) % target => null()
         map % num_free = map % num_free + 1
+        map % num_entries = map % num_entries - 1
 
     end subroutine remove_chaining_entry