Part of the reusable integration policies work.

Reassess how the elements in the Integrations Policies table need to be updated to take in account multiple agent policies.

1. The "Agents" column currently shows the number of agents enrolled to the first available agent policy and it doesn't take in account the other policies. Also, The link brings to the agent list page with a preselected query that currently only gets the first available policy. I think we should:
   • Show the combined number of agents
   • Fix the kuery used to build the link to the agent list page.
2. The "Add agents" action opens the agent flyout, but it takes the id of the first available agent policy. Should we give the user the choice of the agent policy to select instead?
3. The "Upgrade integration" action links to an url that uses the agent policy id. For multiple agent policies currently uses the first available agent policy. Like above, should we update it in some way?