@io_bazel_stardoc transitive depencency is not resolved

Following the instruction, I am trying to use **examples/spring_boot**. (just automatically used Bazel 6.0.0 with Bazelisk, as Bazel 6.0.0 release was today, hence not identified whether caused by new Bazel version)

Basically I took the WORKSPACE file, and adapted it to use rules_jvm_external from respository, as per README.md.

Trying to execute
`bazel fetch @maven//...`
I run into this error message about repository **@io_bazel_stardoc**:
```
C:/users/myuser/_bazel_mlit/5zbjm4tf/external/bazel_tools/tools/build_defs/repo/http.bzl:466:28: in
ERROR: C:/users/myuser/_bazel_mlit/5zbjm4tf/external/maven/BUILD:1373:12: error loading package '@rules_jvm_external//': Unable to find package for @io_bazel_stardoc//stardoc:stardoc.bzl: The repository '@io_bazel_stardoc' could not be resolved: Repository '@io_bazel_stardoc' is not defined. and referenced by '@maven//:defs'
```

Adding this (should NOT be required), the build is running fine:
```
# Load transitive dependency for rules_jvm_external, as it's not resolved automatically
http_archive(
name = "io_bazel_stardoc",
sha256 = "3fd8fec4ddec3c670bd810904e2e33170bedfe12f90adf943508184be458c8bb",
urls = [
"https://mirror.bazel.build/github.com/bazelbuild/stardoc/releases/download/0.5.3/stardoc-0.5.3.tar.gz",
"https://github.com/bazelbuild/stardoc/releases/download/0.5.3/stardoc-0.5.3.tar.gz",
],
)
```

This should be either in your official readme, or better included in your libraries (as transitive version dependency is internal stuff, keeping usage as simple as possible).

Start with examples/spring_boot/WORKSPACE and README.md, then reproduce the issue with Bazel 6.0.0 using `bazel fetch @maven//...`. Trace how rules_jvm_external declares its Stardoc dependency and make the fetch work without manually adding `io_bazel_stardoc`; confirm the documented setup still succeeds.

Written by the indexing model from the issue text.