docs: Api section has wrong links

[itea-dev]

Documentation Feedback

The link to DataSource in table api points to the homepage of angular material.

Affected documentation page: https://material.angular.io/components/table/api

[mmalerba]

The example in the initial issue report no longer exists, but there are still broken links in our API docs: https://material.angular.io/components/table/api#MatCellHarness links to an invalid URL: https://material.angular.io/cdk/testing/api#ContentContainerComponentHarness