Consider adding annotations to the pod template

Hi! We've been using kbld for over two years now with huge success. Thanks! There is just a tiny thing that is bugging us:

**Describe the problem/challenge you have**
As it is usually done, we scrape our **pods** to collect metrics from them. When using `kbld`, the deployed image-**tag** cannot be retrieved just by looking at the pods. Unfortunately, kbld adds its annotations to the owning object (Deployment, StatefulSet, ...) only, but not to its pod template.

Concrete example: We have this manifest:

```yaml
apiVersion: apps/v1
kind: Deployment
metadata:
name: opa
spec:
template:
spec:
containers:
- image: docker.io/openpolicyagent/opa:0.55.0
name: opa
```

When feeding it to kbld, it resolves the tags and adds its annotations:

```yaml
apiVersion: apps/v1
kind: Deployment
metadata:
annotations:
kbld.k14s.io/images: |
- origins:
- resolved:
tag: 0.55.0
url: docker.io/openpolicyagent/opa:0.55.0
url: docker.io/openpolicyagent/opa@sha256:b40919fc5eaf22b70437e81e6575841ad1b034f46b1150873e55fa446cd9f0ca
name: opa
spec:
template:
spec:
containers:
- image: docker.io/openpolicyagent/opa@sha256:b40919fc5eaf22b70437e81e6575841ad1b034f46b1150873e55fa446cd9f0ca
name: opa
```

Instead, I would like to see the annotations *also* (or exclusively, maybe guarded by an option) added to the pod template:

```yaml
apiVersion: apps/v1
kind: Deployment
metadata:
annotations:
kbld.k14s.io/images: |
- origins:
- resolved:
tag: 0.55.0
url: docker.io/openpolicyagent/opa:0.55.0
url: docker.io/openpolicyagent/opa@sha256:b40919fc5eaf22b70437e81e6575841ad1b034f46b1150873e55fa446cd9f0ca
name: opa
spec:
template:
metadata:
annotations:
kbld.k14s.io/images: |
- origins:
- resolved:
tag: 0.55.0
url: docker.io/openpolicyagent/opa:0.55.0
url: docker.io/openpolicyagent/opa@sha256:b40919fc5eaf22b70437e81e6575841ad1b034f46b1150873e55fa446cd9f0ca
spec:
containers:
- image: docker.io/openpolicyagent/opa@sha256:b40919fc5eaf22b70437e81e6575841ad1b034f46b1150873e55fa446cd9f0ca
name: opa
```

I don't really care about the annotations on the outer Manifest. Maybe it should be an option to add the annotations to the pod-template *only*.

**Describe the solution you'd like**
I don't really care if this proposed behaviour gets enabled by default or if this would be opt-in using some kind of option. Maybe this could be configured using a new annotation on the outer manifest, like so:

```yaml
apiVersion: apps/v1
kind: Deployment
metadata:
annotations:
kbld.k14s.io/add-pod-annotations: 'true'
```

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