Profiled builds of haskell_proto_library fail

[aherrmann]

Describe the bug Building a haskell_proto_library target in profiling mode (-c dbg) fails.

To Reproduce

$ bazel test //tests/haskell_proto_library:address_haskell_proto -c dbg
...
bazel-out/k8-dbg/bin/tests/haskell_proto_library/Proto/Tests/HaskellProtoLibrary/ZipCode.hs:10:1: error:
    Could not find module ‘Data.ProtoLens.Runtime.Data.ProtoLens.Prism’
    Perhaps you haven't installed the profiling libraries for package ‘proto-lens-0.6.0.0’?
    Use -v (or `:set -v` in ghci) to see a list of the files searched for.
   |
10 | import qualified Data.ProtoLens.Runtime.Data.ProtoLens.Prism as Data.ProtoLens.Prism
   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
...

Expected behavior The build should succeed.

Environment

• OS name + version: Ubuntu 19.10
• Bazel version: 2.1.0
• Version of the rules: 04f22a04cb12f7782a9a2c581db5f4f564bf69fd

[Xophmeister]

Potentially similar to #1360; if so, see https://github.com/tweag/rules_haskell/issues/1360#issuecomment-912786715 for possible diagnosis