Release notes ordering issue

[wyardley]

What Renovate type are you using?
pro (self-hosted) - 18.x

Describe the bug
With internal (and now some external dependencies), sometimes we'll see release notes repeated, e.g., if there are two releases, the release notes for the most recent are repeated twice under each version.

This one doesn't seem to have GH releases, so maybe it's weirdness with NPM itself?
Compare this:

with
https://github.com/googleapis/nodejs-pubsub/blob/master/CHANGELOG.md
and
https://www.npmjs.com/package/@google-cloud/pubsub

Did you see anything helpful in debug logs?
n/a

To Reproduce

See repro:

• Old entries for typescript-eslint/typescript-eslint: chore(deps): update typescript-eslint monorepo to v4.23.0 viceice-tests/renovate-changelog1#1
• Duplicate entries for traefik: chore(deps): update traefik docker tag to v2.4.6 - autoclosed viceice-tests/renovate-changelog1#2

Additional context
Will try to track down an example of the similar / same issue with an internal repo.

[rarkins]

This might be resolved by #5807. If you can reproduce it in a public repo then I can test it with the CLI to confirm.

[viceice]

Seeing more wrong changelogs, repro: viceice-tests/renovate-changelog1

• Old entries for typescript-eslint/typescript-eslint: chore(deps): update typescript-eslint monorepo to v4.23.0 viceice-tests/renovate-changelog1#1
• Duplicate entries for traefik: chore(deps): update traefik docker tag to v2.4.6 - autoclosed viceice-tests/renovate-changelog1#2

[viceice]

It's manager independend

[viceice]

Missing changelog at all here: renovatebot/github-action#538

Changelog is here: https://github.com/wagoid/commitlint-github-action/blob/master/CHANGELOG.md
Releases are empty.