fix: Improve IAM Policy sync performance (#2826)

#### Summary

This PR adds in server side filtering so that the API doesn't try to get a lot of data that we never use.

In local tests I saw reduction in time from 10 seconds down to 2 seconds

plugins/source/aws/resources/services/iam/policies_fetch.go

@@ -12,7 +12,11 @@ import (
 )
 
 func fetchIamPolicies(ctx context.Context, meta schema.ClientMeta, parent *schema.Resource, res chan<- interface{}) error {
-	var config iam.GetAccountAuthorizationDetailsInput
+	config := iam.GetAccountAuthorizationDetailsInput{
+		Filter: []types.EntityType{
+			types.EntityTypeAWSManagedPolicy, types.EntityTypeLocalManagedPolicy,
+		},
+	}
 	svc := meta.(*client.Client).Services().IAM
 	for {
 		response, err := svc.GetAccountAuthorizationDetails(ctx, &config)