[BUG] [Remote State] Remote state repositories are not being added to cluster state when remote data store is not enabled

[soosinha]

Describe the bug

When remote cluster state and remote data store are both enabled, the remote state and remote routing table repos are added to cluster state and hence showing up in _cat/repositories API.
But when only remote cluster state is enabled and remote data store is disabled, the remote state and remote routing table repos are not being added to cluster state. However the remote state publication is working correctly since it uses the repos from RepositoriesService which get initialized from from RemoteStoreNodeService.createAndVerifyRepositories during bootstrap.
The repos get added to cluster state during the join flow by JoinTaskExecutor. JoinTaskExecutor calls remoteStoreNodeService.updateRepositoriesMetadata to fetch repos to be added to the cluster state. But this function executes only when joining node is a remote store node

OpenSearch/server/src/main/java/org/opensearch/node/remotestore/RemoteStoreNodeService.java

Line 171 in 0c3e3c0

if (joiningNode.isRemoteStoreNode()) {

This logic needs to be changed to check for nodes with only remote state enabled as well.
Similar logic is present here:

OpenSearch/server/src/main/java/org/opensearch/cluster/coordination/JoinTaskExecutor.java

Line 222 in 0c3e3c0

if (remoteDN.isEmpty() && node.isRemoteStoreNode()) {

Related component

Cluster Manager

To Reproduce

1. Create a cluster with remote state enabled, remote publication enabled, remote state repo and remote routing table repo
2. Invoke _cat/repositories API.
3. Remote state and remote routing table repo should not be present in reponse.

Expected behavior

Remote cluster state and routing table repos should get added to cluster state and show up in _cat/repositories API.

Additional Details

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Host/Environment (please complete the following information):

• OS: [e.g. iOS]
• Version [e.g. 22]

Additional context
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