[BUG] Dashboards index name has been changed, breaks backward compatibility with existing clusters

Describe the bug Kibana used to use .kibana* indices in ES cluster, while this behavior is altered after open search name change. Instead of original .kibana* indices, it uses .opensearch_dashboards* indices.

This behavior change causes opensearch dashboards fail to startup if security policy is enforced in the backend cluster.

To Reproduce

1. Start an opensearch cluster with security plugin
2. start OpenSearch Dashboards, it fails due to insufficient permission
3. check opensearch log output, find error as followed:

[2021-04-29T21:34:40,741][INFO ][c.a.o.s.p.PrivilegesEvaluator] [smoketestnode] No permissions for [indices:admin/get]
[2021-04-29T21:34:43,253][INFO ][c.a.o.s.p.PrivilegesEvaluator] [smoketestnode] No index-level perm match for User [name=kibanaserver, backend_roles=[], requestedTenant=null] Resolved [aliases=[], allIndices=[.opensearch_dashboards], types=[*], originalRequested=[.opensearch_dashboards], remoteIndices=[]] [Action [indices:admin/get]] [RolesChecked [own_index, kibana_server]]
[2021-04-29T21:34:43,256][INFO ][c.a.o.s.p.PrivilegesEvaluator] [smoketestnode] No permissions for [indices:admin/get]
[2021-04-29T21:34:45,766][INFO ][c.a.o.s.p.PrivilegesEvaluator] [smoketestnode] No index-level perm match for User [name=kibanaserver, backend_roles=[], requestedTenant=null] Resolved [aliases=[], allIndices=[.opensearch_dashboards], types=[*], originalRequested=[.opensearch_dashboards], remoteIndices=[]] [Action [indices:admin/get]] [RolesChecked [own_index, kibana_server]]

Expected behavior Dashboards should still be using .kibana* indices

OpenSearch Version 1.0.0-beta1

Dashboards Version 1.0.0-beta1

Plugins security plugin v1.0.0.0-beta1

Additional Context Please update any changes needed in security back end after this issue is resolved: https://github.com/opensearch-project/security/issues/1151

Host/Environment (please complete the following information):

• OS: ubuntu:latest docker image as of the day of ticket is opened

[mihirsoni]

@dblock as we have decided to restore it back, this will not be concern anymore, I am assigning this to @kavilla who is currently working on this.

[dblock]

We discussed undoing this change. Assigning the issue to @mihirsoni who had some strong feelings about it to resolve.