add a pull request labeler; add issue tracker links; update codeowners file (#2452)

- add a pull request labeler
- add issue tracker links
- update the codeowners file
- move fake_async to using its own workflow file

Some notes:
- this is multiplexing package test, test_api, and test_core into one
label - `package:test`; not sure if this is desired or not
- this PR doesn't rev. pubspec versions for the `issue_tracker:` change;
I figure that that change will just be picked up with the next general
publish of the packages

---

- [x] I’ve reviewed the contributor guide and applied the relevant
portions to this PR.

<details>
  <summary>Contribution guidelines:</summary><br>

- See our [contributor
guide](https://github.com/dart-lang/.github/blob/main/CONTRIBUTING.md)
for general expectations for PRs.
- Larger or significant changes should be discussed in an issue before
creating a PR.
- Contributions to our repos should follow the [Dart style
guide](https://dart.dev/guides/language/effective-dart) and use `dart
format`.
- Most changes should add an entry to the changelog and may need to [rev
the pubspec package
version](https://github.com/dart-lang/sdk/blob/main/docs/External-Package-Maintenance.md#making-a-change).
- Changes to packages require [corresponding
tests](https://github.com/dart-lang/.github/blob/main/CONTRIBUTING.md#Testing).

Note that many Dart repos have a weekly cadence for reviewing PRs -
please allow for some latency before initial review feedback.
</details>

---------

Co-authored-by: Kevin Moore <[email protected]>

Author: devoncarew

.github/CODEOWNERS

@@ -4,7 +4,7 @@ about: >-
   Report a bug in running tests, integration with a specific platform, or
   any behavior of 'package:test'.
 title: ''
-labels: bug
+labels: bug, package:test
 ---
 Describe the bug in detail.
 Include the specific command you ran and any relevant details about the

.github/ISSUE_TEMPLATE/01_test_runner_bug.md

@@ -4,7 +4,7 @@ about: >-
   Propose a feature for 'package:test' that would make testing easier or more
   powerful.
 title: ''
-labels: enhancement
+labels: enhancement, package:test
 ---
 Describe the feature and include specific description of the use case, or use
 cases, you have in mind.

.github/ISSUE_TEMPLATE/02_test_runner_feature.md

@@ -0,0 +1,5 @@
+---
+name: "package:checks"
+about: "Create a bug or file a feature request against package:checks."
+labels: "package:checks"
+---

.github/ISSUE_TEMPLATE/03_checks_feedback.md

@@ -2,4 +2,4 @@
 name: "package:fake_async"
 about: "Create a bug or file a feature request against package:fake_async."
 labels: "package:fake_async"
----
+---

.github/ISSUE_TEMPLATE/checks.md

@@ -2,4 +2,4 @@
 name: "package:matcher"
 about: "Create a bug or file a feature request against package:matcher."
 labels: "package:matcher"
----
+---

.github/ISSUE_TEMPLATE/fake_async.md

@@ -2,4 +2,4 @@
 name: "package:test_descriptor"
 about: "Create a bug or file a feature request against package:test_descriptor."
 labels: "package:test_descriptor"
----
+---

.github/ISSUE_TEMPLATE/matcher.md

@@ -2,4 +2,4 @@
 name: "package:test_process"
 about: "Create a bug or file a feature request against package:test_process."
 labels: "package:test_process"
----
+---

.github/ISSUE_TEMPLATE/test_descriptor.md

@@ -0,0 +1,31 @@
+# Configuration for .github/workflows/pull_request_label.yml.
+
+'type-infra':
+  - changed-files:
+    - any-glob-to-any-file: '.github/**'
+
+'package:checks':
+  - changed-files:
+    - any-glob-to-any-file: 'pkgs/checks/**'
+
+'package:fake_async':
+  - changed-files:
+    - any-glob-to-any-file: 'pkgs/fake_async/**'
+
+'package:matcher':
+  - changed-files:
+    - any-glob-to-any-file: 'pkgs/matcher/**'
+
+'package:test':
+  - changed-files:
+    - any-glob-to-any-file: 'pkgs/test/**'
+    - any-glob-to-any-file: 'pkgs/test_api/**'
+    - any-glob-to-any-file: 'pkgs/test_core/**'
+
+'package:test_descriptor':
+  - changed-files:
+    - any-glob-to-any-file: 'pkgs/test_descriptor/**'
+
+'package:test_process':
+  - changed-files:
+    - any-glob-to-any-file: 'pkgs/test_process/**'