Add submodules support to health.yaml

[mosuem]

For setups as in dart-lang/i18n#740

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[github-actions]

PR Health

Breaking changes ✔️

Details

Package	Change	Current Version	New Version	Needed Version	Looking good?

Changelog Entry ✔️

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Package	Changed Files

Changes to files need to be accounted for in their respective changelogs.

Coverage ✔️

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File	Coverage

This check for test coverage is informational (issues shown here will not fail the PR).

License Headers ✔️

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// Copyright (c) 2024, the Dart project authors. Please see the AUTHORS file
// for details. All rights reserved. Use of this source code is governed by a
// BSD-style license that can be found in the LICENSE file.

Files
no missing headers

All source files should start with a license header.

Package publish validation ✔️

Details

Package	Version	Status
package:dart_flutter_team_lints	2.1.1	already published at pub.dev
package:firehose	0.5.2	already published at pub.dev

Documentation at https://github.com/dart-lang/ecosystem/wiki/Publishing-automation.