Bazel Docs: Add missing generated files to 9.0 release docs.

6e1e226 built the initial 9.0 docs, but missed all generated docs under rules/lib/repo because the html2mdx tool ignored all .md files.

Since then we've upgraded html2mdx to docs2mdx, so I could cherry-pick those additional commits to recreated the 9.0 docs:

<details>

<summary>Commands</summary>

```
git checkout release-9.0.0
# remove file that should be generated, but was checked in by mistake:
rm docs/reference/command-line-reference.mdx
# revert 9.1.0 change:
git revert 87aad18
git cherry-pick bc436e3 \
  a4e5d84 \
  8ca49ef \
  4c6b39b \
  8f80aea \
  1c114e3 \
  e602c70

bazel build \
  --config=docs \
  //scripts/docs:gen_mdx_release_docs
```

</details>

PiperOrigin-RevId: 895876591

Author: fweikert

docs/versions/9.0.0/rules/lib/repo/cache.mdx

@@ -0,0 +1,74 @@
+---
+title: 'cache repository rules'
+---
+
+The following functions can be loaded from
+`@bazel_tools//tools/build_defs/repo:cache.bzl`.
+
+Returns the default canonical id to use for downloads.
+
+<a id="get_default_canonical_id"></a>
+
+## get_default_canonical_id
+
+<pre>
+load("@bazel//tools/build_defs/repo:cache.bzl", "get_default_canonical_id")
+
+get_default_canonical_id(<a href="#get_default_canonical_id-repository_ctx">repository_ctx</a>, <a href="#get_default_canonical_id-urls">urls</a>)
+</pre>
+
+Returns the default canonical id to use for downloads.
+
+Returns `""` (empty string) when Bazel is run with
+`--repo_env=BAZEL_HTTP_RULES_URLS_AS_DEFAULT_CANONICAL_ID=0`.
+
+e.g.
+```python
+load("@bazel_tools//tools/build_defs/repo:cache.bzl", "get_default_canonical_id")
+# ...
+    repository_ctx.download_and_extract(
+        url = urls,
+        integrity = integrity
+        canonical_id = get_default_canonical_id(repository_ctx, urls),
+    ),
+```
+
+### Parameters
+
+<table class="params-table">
+<colgroup>
+<col class="col-param" />
+<col class="col-description" />
+</colgroup>
+<tbody>
+<tr id="get_default_canonical_id-repository_ctx">
+<td><code>repository_ctx</code></td>
+<td>
+
+required.
+
+<p>
+
+The repository context of the repository rule calling this utility
+function.
+
+</p>
+</td>
+</tr>
+<tr id="get_default_canonical_id-urls">
+<td><code>urls</code></td>
+<td>
+
+required.
+
+<p>
+
+A list of URLs matching what is passed to `repository_ctx.download` and
+`repository_ctx.download_and_extract`.
+
+</p>
+</td>
+</tr>
+</tbody>
+</table>
+