Get a full accounting of requests that are of type IndicesRequest, but not IndicesRequest.Replaceable

[cwperks]

Is your feature request related to a problem?

Filing this issue in response to #5076. In that PR, a bugfix for RolloverRequests was added to help the security plugin resolve the request to a set of concrete indices. The security plugin has a fairly convoluted method for resolving a generic ActionRequest to a set of indices that the ActionRequest is pertinent to. The reason this method is convoluted is because there isn't a great hierarchy of ActionRequests to group all requests pertaining to indices in one singular category with a convenient method to extract the index patterns that the request is operating on.

On a high-level, requests are categorized into Cluster requests and Index Requests, but there isn't a form hierarchy that actually reflects this.

To account for this, the IndexResolverReplacer has a big switch-case type method that examines the type of request and knows how to extract the indices. For the most part, if a request is an IndicesRequest it is also an IndicesRequest.Replaceable which is already accounted for in the switch-case, but that is not true in all cases.

I'm opening up this issue to get a full accounting of the requests in core that are of type IndicesRequest, but not IndicesRequest.Replaceable to determine if we need to add more clauses to the IndexResolverReplacer or if there should be a catch all at the bottom for IndicesRequests.