fix(ng-update): material update fails due to circular dependency

[devversion]

Currently running ng update for both Material and CDK fails because there
is a circular dependency in the CDK schematics that cause the update-tool
exports to be not available to the Material ng-update schematic.

Without putting to much effort into ensuring no circular dependencies, this
commit also sets up Madge to avoid such issues in the future.

[devversion]

I decided to just add this one-liner as that command helped me finding the circular dependency that broke the Material update. Long-term solution should definitely be different.

[jelbourn]

LGTM

[devversion]

To clarify: I did various manual testings after the ng-update rework but such issues are not easy to test with packages which are not published on NPM as ng update behaves differently if it installs packages through NPM or uses local ones.

Ideally we'll have some real integration tests for this. And next time I'll make sure to push the schematics to a NPM package for manual testing (even though it's way more effort..)

[angular-automatic-lock-bot]

This issue has been automatically locked due to inactivity.
Please file a new issue if you are encountering a similar or related problem.

Read more about our automatic conversation locking policy.

_{This action has been performed automatically by a bot.}