Check that tracking says no event and writes nothing, as ADR 0285 states

modules/mesh-issues/cmd/mesh-issues/tracking_test.go

@@ -2,6 +2,7 @@ package main
 
 import (
 	"encoding/json"
+	"reflect"
 	"strings"
 	"testing"
 	"time"
@@ -137,10 +138,15 @@ func TestTheTrackingVerb(t *testing.T) {
 	if _, err := h.Note(n, "the share's password=hunter2 was typed here"); err != nil {
 		t.Fatal(err)
 	}
+	events, before := len(h.said()), h.mem.snapshot(IssuesState)
 	out, err := h.call(t, "tracking", map[string]any{})
 	if err != nil {
 		t.Fatal(err)
 	}
+	// A read: no event said, nothing written.
+	if len(h.said()) != events || !reflect.DeepEqual(h.mem.snapshot(IssuesState), before) {
+		t.Fatal("tracking said an event or wrote an issue")
+	}
 	raw, _ := json.Marshal(out)
 	if !strings.Contains(string(raw), `"`+mountsKey+`":[{"number":`) {
 		t.Fatalf("%s", raw)