Backport of docs: fix the description of client rpc into release/1.15.x

[hc-github-team-consul-core]

Backport

This PR is auto-generated from #18206 to be assessed for backporting due to the inclusion of the label backport/1.15.

The below text is copied from the body of the original PR.

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Description

The metric consul.client.rpc is applicable to consul server as well, so remove in client mode in the metric description, which makes it sounds like client agent only.

consul/agent/consul/server.go

Lines 1802 to 1818 in ada767f

	func (s *Server) RPC(ctx context.Context, method string, args interface{}, reply interface{}) error {
	remoteAddr, _ := RemoteAddrFromContext(ctx)
	codec := &inmemCodec{
	method: method,
	args: args,
	reply: reply,
	sourceAddr: remoteAddr,
	}
	// Enforce the RPC limit.
	//
	// "client" metric path because the internal client API is calling to the
	// internal server API. It's odd that the same request directed to a server is
	// recorded differently. On the other hand this possibly masks the different
	// between regular client requests that traverse the network and these which
	// don't (unless forwarded). This still seems most reasonable.
	metrics.IncrCounter([]string{"client", "rpc"}, 1)

Testing & Reproduction steps

Links

PR Checklist

• updated test coverage
• external facing docs updated
• appropriate backport labels added
• not a security concern

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Overview of commits

• 4e8cddd

[github-team-consul-core-pr-approver]

Auto approved Consul Bot automated PR

[hc-github-team-consul-core]

🤔 This PR has changes in the website/ directory but does not have a type/docs-cherrypick label. If the changes are for the next version, this can be ignored. If they are updates to current docs, attach the label to auto cherrypick to the stable-website branch after merging.