Work around invalid path problem on Windows

```
ERROR: Invalid path in C:/_bzl/minshlu6/external/rules_nixpkgs_core~/.bazelignore: java.nio.file.InvalidPathException: Illegal char <*> at index 6: bazel-*
```

Author: avdv

haskell/repositories.bzl

@@ -108,6 +108,8 @@ def rules_haskell_dependencies():
             strip_prefix = strip_prefix + "/core",
             urls = [rules_nixpkgs_url],
             sha256 = _rules_nixpkgs_sha256,
+            # work around invalid path on Windows
+            patch_cmds_win = ["del /f /q .bazelignore"],
         )
 
         for toolchain in ["cc", "java", "python", "go", "rust", "posix", "nodejs"]:
@@ -116,6 +118,8 @@ def rules_haskell_dependencies():
                 strip_prefix = strip_prefix + "/toolchains/" + toolchain,
                 urls = [rules_nixpkgs_url],
                 sha256 = _rules_nixpkgs_sha256,
+                # work around invalid path on Windows
+                patch_cmds_win = ["del /f /q .bazelignore"],
             )
 
     maybe(