Recursively extract tasks from blocks

[cognifloyd]

allow matchtask() to match embedded tasks

- block:
  - block:
    - template:
        src: ...

See for example:
https://github.com/ansible-community/ansible-lint/blob/ff90dd4a5b1f105028a4c4d5d70a9cd2bcb69bdb/examples/roles/role_for_no_same_owner/tasks/fail.yml#L13-L19

The no-same-owner rule, added in #1450, uses that test tasks file. It does its own task parsing to ensure it can recursively find tasks. We should allow all rules to recursively find tasks.

[ssbarnea]

This change needs a modification of at least one test that will verify the fixed bug or we risk breaking it in the future.

Can you modify one test or add a new one that ensures that this change fixes a bug? The test should fail without it and pass after this change goes in.

If I understood correctly it should be ok to modify one example and add a deep bug that is not found without this change.

[cognifloyd]

LOL. I updated CommandHasChangesCheckRule to detect command tasks in blocks... and now lots of tests are failing because we don't have changed_when in most of the examples.

[ssbarnea]

Updating one rule/test to make use of it should be enough to prevent regression. Feel free to add changed_when: false or to update the tests to count for the new number of failures.

[cognifloyd]

I only had to update 1 playbook. 😌 Tests are green now.