fixup! OxCaml: setup CI

Author: vouillon

tools/ci_setup-oxcaml.ml

@@ -241,6 +241,16 @@ index 7996514..d0b463a 100644
 + (library (name zarith_wrapper)
 +  (wrapped false)
 +  (libraries zarith)))
+diff --git a/test/zarith.ml b/test/zarith.ml
+index 059d011..b40264e 100644
+--- a/test/zarith.ml
++++ b/test/zarith.ml
+@@ -1,5 +1,4 @@
+ module Big_int_Z = Big_int_Z
+ module Q = Q
+ module Z = Z
+-module Zarith = Zarith
+ module Zarith_version = Zarith_version
 |zs}
     )
   ]