ci: rename material-unit-tests job to components-repo-unit-tests (#34898)

We rename the `material-unit-tests` job to `components-repo-unit-tests`
because the job runs all unit tests found in the Angular Components repository.
This includes the Angular CDK, Angular Material and more. Also the repository has
been renamed from `angular/material2` to `angular/components` in the past.

PR Close #34898

tools/components-repo-ci/instructions.md

@@ -0,0 +1,32 @@
+### Unit tests for `angular/components`
+
+Currently, all changes to Ivy are validated against the test suite of the
+`angular/components` repository. Known failing tests are skipped based on
+the blocklist in `tools/components-repo-ci/test-blocklist.ts`.
+
+Whenever the root cause of a known failure is identified, the `notes` field
+for the corresponding tests should be updated. Whenever a failure is resolved,
+the corresponding tests should be removed from the blocklist.
+
+### Debugging
+
+Information on debugging can be found [here](../../docs/DEBUG_COMPONENTS_REPO_IVY.md).
+
+### Excluding new tests
+
+In case there are any tests in the components test suite that fail due to
+recent changes in the framework and you want to exclude the tests temporarily,
+a new entry can be added to the `test-blocklist.ts` file.
+
+Each property in the blocklist object corresponds to a test in the components
+repository. The name of the property **must** match the exact test name. Additionally
+it's **recommended** that every entry has a field with a note on why the test is disabled.
+
+```ts
+export const testBlocklist: any = {
+  'MatSlider should be able to drag thumb': {
+    error: 'Cannot register event "dragstart".',
+    notes: 'Breaking change where HammerJS module needs to be imported.'
+  }
+}
+```

tools/components-repo-ci/test-blocklist.ts

@@ -0,0 +1,29 @@
+/**
+ * @license
+ * Copyright Google Inc. All Rights Reserved.
+ *
+ * Use of this source code is governed by an MIT-style license that can be
+ * found in the LICENSE file at https://angular.io/license
+ */
+
+// clang-format off
+// tslint:disable
+
+interface BlocklistEntry {
+  /** Description on why the given test is disabled. */
+  notes: string;
+  /** Optional error that has been thrown in the test. */
+  error?: string;
+}
+
+/**
+ * List of tests that should not run in the Angular component test suites. This should
+ * be empty in the components repository, but the file will be overwritten if the framework
+ * repository runs the Angular component test suites against the latest snapshots. This is
+ * helpful because sometimes breaking changes that break individual tests land in the framework
+ * repository. It should be possible to disable these tests until the component repository
+ * migrated the broken tests.
+ */
+export const testBlocklist: {[testName: string]: BlocklistEntry} = {};
+
+// clang-format on