Unable to build using rules_go in my own repo

### What version of rules_go are you using?
Same as master branch. I forked to my own repo.

### What version of gazelle are you using?

### What version of Bazel are you using?
6.0.0

### Does this issue reproduce with the latest releases of all the above?

### What operating system and processor architecture are you using?
Mac OS

### Any other potentially useful information about your toolchain?

### What did you do?
I'm trying to contribute to [rules_go](https://github.com/bazelbuild/rules_go), On my local pc, I'm using http_archive to fetch rules from my own repo. Here is a demo [repo](https://github.com/YuanHao97/bazel-17571), Try 'bazel run //:runfiles' then you can see the error message

### What did you expect to see?

Something like this: /private/var/tmp/_bazel_yh/54a82a2cd277eb13b8a17e535157729f/external/go_sdk/bin/gofmt.

### What did you see instead?
ERROR: Error computing the main repository mapping: Every .bzl file must have a corresponding package, but '@io_bazel_rules_go//go:deps.bzl' does not have one. Please create a BUILD file in the same or any parent directory. Note that this BUILD file does not need to do anything except exist.

Start with the linked demo repository and run `bazel run //:runfiles` on Bazel 6.0.0 to reproduce the repository-mapping error. Inspect the WORKSPACE `http_archive` setup for the forked rules and compare it with the expected rules_go layout. Done means the command builds and reports the gofmt path instead of the missing BUILD-file error.

Written by the indexing model from the issue text.