Apply CRDs directly without the applier manager

[twz123]

Description

There's no need to write them to the filesystem. Moreover, we can be sure that whenever the CRD component is initialized, the CRDs have been applied successfully, so we don't need to wait for the applier manager to pick things up.

Add the etcd member reconciler as a cluster component, just as its CRD stack. This ensures that the CRDs get applied before the reconciler is started.

Move unstructured stack application into public function The system RBAC component fed an io.Reader into a resource builder to extract unstructured objects and apply them as a stack in a retry loop. This is a pattern that is reusable across components: Move this into its own function in the applier package.

Type of change

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• Documentation update

How Has This Been Tested?

• Manual test
• Auto test added

Checklist

• My code follows the style guidelines of this project
• My commit messages are signed-off
• I have performed a self-review of my code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• My changes generate no new warnings
• I have added tests that prove my fix is effective or that my feature works
• New and existing unit tests pass locally with my changes
• Any dependent changes have been merged and published in downstream modules
• I have checked my code and corrected any misspellings