test: fix brittle tests (#8166)

These tests relied on the fact that the retry option was the first. It is likely in the future orders will change even more so these tests should eventually be written or removed. We should exercies that retries work more generally if we don't already.

Fixes: #8095
Fixes: #8146

pubsub/pubsub_test.go

@@ -53,13 +53,13 @@ func TestClient_CustomRetry(t *testing.T) {
 
 	cs := &gax.CallSettings{}
 	// This is the default retry setting.
-	c.pubc.CallOptions.Publish[0].Resolve(cs)
+	c.pubc.CallOptions.Publish[1].Resolve(cs)
 	if got, want := fmt.Sprintf("%v", cs.Retry()), "&{{100000000 60000000000 1.3 0} [10 1 13 8 2 14 4]}"; got != want {
 		t.Fatalf("got: %v, want: %v", got, want)
 	}
 
 	// This is the custom retry setting.
-	c.pubc.CallOptions.Publish[1].Resolve(cs)
+	c.pubc.CallOptions.Publish[2].Resolve(cs)
 	if got, want := fmt.Sprintf("%v", cs.Retry()), "&{{200000000 30000000000 1.25 0} [14 4]}"; got != want {
 		t.Fatalf("merged CallOptions is incorrect: got %v, want %v", got, want)
 	}

spanner/client_test.go

@@ -2736,13 +2736,13 @@ func TestClient_CallOptions(t *testing.T) {
 
 	cs := &gax.CallSettings{}
 	// This is the default retry setting.
-	c.CallOptions.CreateSession[0].Resolve(cs)
+	c.CallOptions.CreateSession[1].Resolve(cs)
 	if got, want := fmt.Sprintf("%v", cs.Retry()), "&{{250000000 32000000000 1.3 0} [14]}"; got != want {
 		t.Fatalf("merged CallOptions is incorrect: got %v, want %v", got, want)
 	}
 
 	// This is the custom retry setting.
-	c.CallOptions.CreateSession[1].Resolve(cs)
+	c.CallOptions.CreateSession[2].Resolve(cs)
 	if got, want := fmt.Sprintf("%v", cs.Retry()), "&{{200000000 30000000000 1.25 0} [14 4]}"; got != want {
 		t.Fatalf("merged CallOptions is incorrect: got %v, want %v", got, want)
 	}