[ISSUE-1018] Refine Storage Group Feature Release OBS 1.3

[CraneShiEMC]

Purpose

Resolves #1018

Refine Storage Group Feature:

1. Add StorageGroupStatus
2. If we perform drive removal on the drive selected by some storagegroup with numberDrivesPerNode>0, the storagegroup's reconcilation should be triggered and it can select another drive if applicable.
3. Block StorageGroupSpec Update
4. Add StorageGroupController UT
5. Use k8s caching client reader in storagegroup controller
6. For the drive with existing volumes that matches the driveSelector of some storage group, the drive should be selected into its matching storage group when its exsiting volumes removed.
7. The blocked storagegroup deletion can continue instantly after all exisitng volumes on drives of this storage group is removed.

PR checklist

• Add link to the issue
• Choose Project
• Choose PR label
• New unit tests added
• Modified code has meaningful comments
• All TODOs are linked with the issues
• All comments are resolved

Testing

Manual test passed.
Custom CI passed: https://asd-ecs-jenkins.isus.emc.com/job/csi-custom-ci/1559/
Custom Acceptance Passed: https://asd-ecs-jenkins.isus.emc.com/job/csi-custom-acceptance-tar_b_ona/36/