Kapp shows "update" operation for ConfigMap that has no changes

**What steps did you take:**

I have a simple, static ConfigMap where kapp insists that deploying the ConfigMap will result in an `update` operation, although the ConfigMap is exactly the same as the deployed one. If I deploy the file multiple times in a row, kapp still announces the `update` operation every time.

**What did you expect:**

When the ConfigMap has not changed, kapp should not show an `update` operation.

**Anything else you would like to add:**

Using `kapp deploy -c` shows the removal of an empty `metadata.annotations` element:

```
kapp deploy -a clustering -f configmap.yaml -c
Target cluster 'https://127.0.0.1:6443' (nodes: mngr1.censored 8+)

@@ update configmap/clustering-cacerts-m7b68mk2mm (v1) namespace: default @@
...
4776,4776 metadata:
4777 - annotations: {}
4778,4777 creationTimestamp: "2022-09-12T14:26:59Z"
4779,4778 labels:

Changes

Namespace Name Kind Age Op Op st. Wait to Rs Ri
default clustering-cacerts-m7b68mk2mm ConfigMap 16m update - reconcile ok -
```

I don't know where this `annotations` field comes from. The metadata of our ConfigMap does not include an `annotations` field:
```yaml
kind: ConfigMap
metadata:
labels:
app.kubernetes.io/part-of: clustering
name: clustering-cacerts-m7b68mk2mm
namespace: default
```
Kapp seems to think that the absence of an `annotations` field is different from an *empty* one.

**Environment:**

- kapp version (use `kapp --version`): kapp version 0.52.0
- OS (e.g. from `/etc/os-release`): AlmaLinux 8.6 (Sky Tiger)
- Kubernetes version (use `kubectl version`): `Server Version: version.Info{Major:"1", Minor:"24", GitVersion:"v1.24.1+k3s1", GitCommit:"0581808f5c160b0c0cafec5b8f20430835f34f44", GitTreeState:"clean", BuildDate:"2022-06-11T17:26:28Z", GoVersion:"go1.18.1", Compiler:"gc", Platform:"linux/amd64"}`

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