chore: use preconfigured policy for fleet-server's default policy

cli/config/compose/profiles/fleet/default/kibana.config.yml

@@ -16,3 +16,16 @@ xpack.fleet.agents.fleet_server.hosts: ["http://fleet-server:8220"]
 
 xpack.encryptedSavedObjects.encryptionKey: "12345678901234567890123456789012"
 xpack.fleet.agents.tlsCheckDisabled: true
+
+xpack.fleet.packages:
+  - name: fleet_server
+    version: latest
+xpack.fleet.agentPolicies:
+  - name: Fleet Server policy
+    id: fleet-server-policy
+    description: Fleet server policy
+    namespace: default
+    package_policies:
+      - name: Fleet Server
+        package:
+          name: fleet_server

cli/config/compose/profiles/fleet/preconfigured-policies/kibana.config.yml

@@ -22,6 +22,9 @@ xpack.fleet.outputs:
     type: "elasticsearch"
     id: "output-123"
     hosts: ["http://elasticsearch:9200"]
+xpack.fleet.packages:
+  - name: fleet_server
+    version: latest
 xpack.fleet.agentPolicies:
   - name: Test preconfigured policy
     id: "test-preconfigured"
@@ -32,3 +35,11 @@ xpack.fleet.agentPolicies:
       - package:
           name: system
         name: sytem-1
+  - name: Fleet Server policy
+    id: fleet-server-policy
+    description: Fleet server policy
+    namespace: default
+    package_policies:
+      - name: Fleet Server
+        package:
+          name: fleet_server

e2e/_suites/fleet/fleet.go

@@ -651,12 +651,13 @@ func bootstrapFleet(ctx context.Context, env map[string]string) error {
 			}).Fatal("Fleet could not be recreated")
 		}
 
-		fleetServicePolicy, err := kibanaClient.GetDefaultPolicy(ctx, true)
-		if err != nil {
-			log.WithFields(log.Fields{
-				"error": err,
-			}).Fatal("Could not get Fleet Server's default policy")
+		// these values comes from the kibana.config.yml file at Fleet's profile dir
+		fleetServicePolicy := kibana.Policy{
+			ID:          "fleet-server-policy",
+			Name:        "Fleet Server Policy",
+			Description: "Fleet Server policy",
 		}
+
 		log.WithFields(log.Fields{
 			"id":          fleetServicePolicy.ID,
 			"name":        fleetServicePolicy.Name,

internal/kibana/policies.go

@@ -31,6 +31,7 @@ type Policy struct {
 }
 
 // GetDefaultPolicy gets the default policy or optionally the default fleet policy
+// deprecated: will be removed in upcoming releases
 func (c *Client) GetDefaultPolicy(ctx context.Context, fleetServer bool) (Policy, error) {
 	span, _ := apm.StartSpanOptions(ctx, "Getting default policy", "fleet.package-policies.get-default", apm.SpanOptions{
 		Parent: apm.SpanFromContext(ctx).TraceContext(),