[new commit] Update LokiStack configuration with global limits for retention and managementState

Doc Reference: https://docs.redhat.com/en/documentation/red_hat_openshift_logging/6.3/html/installing_logging/installing-logging#install-loki-operator-cli_installing-logging

By default, the retention config is not mentioned in standard installation YAML because of which end users use the exact same config for deployment and then object storage get flooded with a lot of logs. This breaks ODF and impacts the applications consuming storage from ODF.

It is required to add retention config in standard installation YAML in the documentation. If there is no retention, then the logs will not be remove / cleaned up from object storage until retention is configured or until lifecycle policy is configured on the object bucket.

Here is the updated config:

~~~
apiVersion: loki.grafana.com/v1
kind: LokiStack
metadata:
  name: logging-loki  1 
  namespace: openshift-logging  2 
spec:
  managementState: Managed 
  limits:  
    global:   3
      retention:   4
        days: 20   # Set the value as per requirement.
  size: 1x.small  5 
  storage:
    schemas:
    - version: v13
      effectiveDate: "<yyyy>-<mm>-<dd>"  6
    secret:
      name: logging-loki-s3  7
      type: s3  8 
  storageClassName: <storage_class_name>  9 
  tenants:
    mode: openshift-logging  10
~~~

Author: prithvipatil97

modules/installing-loki-operator-cli.adoc

@@ -168,7 +168,7 @@ spec:
 ----
 <1> Use the name `logging-loki`.
 <2> You must specify `openshift-logging` as the namespace.
-<3> Define global limits that apply to the LokiStack instance. *Note: This field does not impact the retention period for stored logs in object storage.*
+<3> Define global limits that apply to the LokiStack instance. For information about setting stream-based retention, see link:https://docs.redhat.com/en/documentation/red_hat_openshift_logging/6.3/html/configuring_logging/configuring-lokistack-storage#logging-loki-retention_configuring-the-log-store[Enabling stream-based retention with Loki]. This field does not impact the retention period for stored logs in object storage.
 <4> Retention is enabled in the cluster when this block is added to the CR.
 <5> Specify the deployment size. Supported size options for production instances of Loki are `1x.extra-small`, `1x.small`, or `1x.medium`. Additionally, `1x.pico` is supported starting with {logging} 6.1.
 <6> For new installations this date should be set to the equivalent of "yesterday", as this will be the date from when the schema takes effect.