Disable use of pkg-config for zlib

In recent versions haskell zlib is using pkg-config to locate the C zlib but thoughtfully there
is a flag to disable it.

Author: avdv

rules_haskell_tests/non_module_deps_2.bzl

@@ -31,6 +31,8 @@ def repositories(*, bzlmod):  # @unused
         local_snapshot = "//:stackage_snapshot{}.yaml".format(
             "_" + str(GHC_VERSION) if GHC_VERSION else "",
         ),
+        # disable calling pkg-config
+        flags = {"zlib": ["-pkg-config"]},
         packages = ["zlib"],
         stack_snapshot_json = ("//:stackage-zlib-snapshot{}.json".format(
             "_" + str(GHC_VERSION) if GHC_VERSION else "",

start

@@ -271,6 +271,9 @@ stack_snapshot(
     extra_deps = {"zlib": ["@zlib.dev//:zlib"]},
     packages = ["zlib"],
 
+    # disable calling pkg-config
+    flags = {"zlib": ["-pkg-config"]},
+
     # LTS snapshot published for ghc-${GHC_VERSION} (default version used by rules_haskell)
     snapshot = "$SNAPSHOT",