Add getClusters feature

[cambelem]

Description

This feature introduces a new command to retrieve a list of Cluster attributes based on organization_id.

Key Features

• Defaults Output: JSON format.
• Added --first flag for the first cluster in the list
• Added searchStr for getClusters

Usage Examples:

Input:
ocm-support get clusters [org_id]

Result:

[
  {
    "id": "1 ... a",
    "href": "/api/clusters_mgmt/v1/clusters/[cluster_id]",
    "name": "cluster-name1",
    "external_id": "1 ... c"
    "display_name": "cluster-name1",
    "subscription_id": "1 ... b",
    "state": "ready",
    "cloud_provider": "aws",
    "version": "4.16.0",
    "region_id": "us-east-1",
    "multi_az": true,
    "product_id": "rosa",
    "managed": true,
    "console_url": "https://console-openshift-console.apps.cluster-name1.com",
    "creation_timestamp": "2024-07-01T01:00:00.000000Z",
  },
...
]

Input:
ocm-support get clusters [org_id] --first

Result:

[
  {
    "id": "1 ... a",
    "href": "/api/clusters_mgmt/v1/clusters/[cluster_id]",
    "name": "cluster-name1",
    "external_id": "1 ... c"
    "display_name": "cluster-name1",
    "subscription_id": "1 ... b",
    "state": "ready",
    "cloud_provider": "aws",
    "version": "4.16.0",
    "region_id": "us-east-1",
    "multi_az": true,
    "product_id": "rosa",
    "managed": true,
    "console_url": "https://console-openshift-console.apps.cluster-name1.com",
    "creation_timestamp": "2024-07-01T01:00:00.000000Z",
  }
]

Input:
ocm-support get clusters [org_id] "region.id='us-east-1'"

Result:

[
  {
    "id": "1 ... a",
    "href": "/api/clusters_mgmt/v1/clusters/[cluster_id]",
    "name": "cluster-name1",
    "external_id": "1 ... c"
    "display_name": "cluster-name1",
    "subscription_id": "1 ... b",
    "state": "ready",
    "cloud_provider": "aws",
    "version": "4.16.0",
    "region_id": "us-east-1",
    "multi_az": true,
    "product_id": "rosa",
    "managed": true,
    "console_url": "https://console-openshift-console.apps.cluster-name1.com",
    "creation_timestamp": "2024-07-01T01:00:00.000000Z",
  },
...
]

[tirthct]

In addition to these file changes, we can also update the readme with a section about this command

[cristianoveiga]

LGTM