[Bug]: key "freebsd_amd64" not found in dictionary

### What happened?

I added an `http_archive` that loads this repository transitively. In one of the function calls, it uses [copy_directory_platform_repo](https://github.com/aspect-build/bazel-lib/blob/main/lib/private/copy_directory_toolchain.bzl), but raises the error in the title.

This happens because [COPY_DIRECTORY_PLATORMS](https://github.com/aspect-build/bazel-lib/blob/8fa21275181371b38f76ef30d0aa14006a2b472b/lib/private/copy_directory_toolchain.bzl#L12) has the key `freebsd_amd64`, but `COPY_DIRECTORY_INTEGRITY` used [here](https://github.com/aspect-build/bazel-lib/blob/8fa21275181371b38f76ef30d0aa14006a2b472b/lib/private/copy_directory_toolchain.bzl#L170) and declared [here](https://github.com/aspect-build/bazel-lib/blob/main/tools/versions.bzl) does not.

### Version

Dev architecture: MacOS arm64

```
bazel --version
bazel 6.3.2-homebrew
```

Tool that I want to install:
```
http_archive(
name = "aspect_rules_js",
sha256 = "77c4ea46c27f96e4aadcc580cd608369208422cf774988594ae8a01df6642c82",
strip_prefix = "rules_js-1.32.2",
url = "https://github.com/aspect-build/rules_js/releases/download/v1.32.2/rules_js-v1.32.2.tar.gz",
)
```

`aspect_bazel_lib` loaded transitively:
```
http_archive(
name = "aspect_bazel_lib",
sha256 = "44f4f6d1ea1fc5a79ed6ca83f875038fee0a0c47db4f9c9beed097e56f8fad03",
strip_prefix = "bazel-lib-1.34.0",
url = "https://github.com/aspect-build/bazel-lib/releases/download/v1.34.0/bazel-lib-v1.34.0.tar.gz",
)
```

The error happens when `bazel sync`ing.

The version downloaded there is different from the latest one here, but I think the code would yield the same error given that the key does not exist.

### How to reproduce

```shell
WORKSPACE

http_archive(
name = "aspect_rules_js",
sha256 = "77c4ea46c27f96e4aadcc580cd608369208422cf774988594ae8a01df6642c82",
strip_prefix = "rules_js-1.32.2",
url = "https://github.com/aspect-build/rules_js/releases/download/v1.32.2/rules_js-v1.32.2.tar.gz",
)

load("@aspect_rules_js//js:repositories.bzl", "rules_js_dependencies")
```

OS: MacOS arm64 (Apple M2 Max)
```

Read lib/private/copy_directory_toolchain.bzl, especially COPY_DIRECTORY_PLATFORMS and the lookup around line 170, then inspect tools/versions.bzl for COPY_DIRECTORY_INTEGRITY. Reproduce the failure with the supplied WORKSPACE and bazel sync; done means the freebsd_amd64 entry is handled without the dictionary error.

Written by the indexing model from the issue text.