Not able to update cluster-token from UI if needed

[dheeth]

Checklist:

• I've searched in the docs and FAQ for my answer
• I've included steps to reproduce the bug.

Describe the bug

If we update a token for any cluster, it throws response 500 error. It updates the token in database but doesn't update the token in respective secret of the cluster

To Reproduce

1. Add a cluster to Devtron
2. Generate a new token for the same cluster
3. Update it in cluster configurations

Expected behavior

It should update the token and continue the normal functioning

Current behavior

It throws an error on update, then updates only in database but not in respective secret of the cluster