fix: Switch to distroless image in Dockerfile [PC-13119] (#137)

## Motivation

Currently, we're missing certificates in our Docker image, so it won't
work.

```
Post "https://accounts.nobl9.com/oauth2/auseg9kiegWKEtJZC416/v1/token": tls: failed to verify certificate: x509: certificate signed by unknown authority
```

## Summary

Switch to
[distroless](https://github.com/GoogleContainerTools/distroless) image
which has certificates baked in.

## Related changes

Similar problem I've encountered recently in another project:
nieomylnieja/go-libyear@c7faae7

## Testing

```shell
make docker
docker run -e SLOCTL_CLIENT_ID=$CLIENT_ID -e SLOCTL_CLIENT_SECRET=$CLIENT_SECRET sloctl get slos
```

## Release Notes

Fixed missing TLS certificates from Docker image.

Dockerfile

@@ -13,7 +13,7 @@ RUN CGO_ENABLED=0 go build \
   -o /artifacts/sloctl \
   "${PWD}/cmd/sloctl"
 
-FROM scratch
+FROM gcr.io/distroless/static-debian12
 
 COPY --from=builder /artifacts/sloctl /usr/bin/sloctl
 

cspell.yaml

@@ -28,6 +28,7 @@ ignorePaths:
   - "**/test_data/**"
   - dist/**
 words:
+  - distroless
   - dynatrace
   - endef
   - gobin