Automatic merge from submit-queue
Cleanup fluentd-gcp image, rebase on debian-base
**Why we need this PR**:
There are several problems with our current fluentd-gcp image:
- It pulls in lots of unused packages, which expose unnecessary risk and create noise in CVE scans (and scare customers). The most notable example is the fluent-ui, which pulls in rails.
- `curl | sh ` is not a good practice for a Dockerfile. First, the script is not checked in the same source control branch, so builds are not reproducible. Second, the actions it is taking are opaque. Third, in this case, using non-standard packages means they're harder to manage with CVE scans & upstream fixes.
**What is changed by this PR?**
- Rather than relying on td-agent (which includes fluent-ui), use standard upstream packages. This is largely based off the [official fluentd debian-based image](https://github.com/fluent/fluentd-docker-image/blob/master/v0.12/debian/Dockerfile).
- Rebases the image on debian-base (depends on https://github.com/kubernetes/kubernetes/pull/41915). We would like to move towards a single full-distro base image we can maintain. This change should be relatively minor.
As a result of these changes, the image size is reduced from 360.6 MB to 185.8 MB (nearly half). Many packages were removed, and the full diff (focus on the unversioned files) is listed here: 3fb704f977
**Which issue this PR fixes** https://github.com/kubernetes/kubernetes/issues/40248
**Special notes for your reviewer**:
This change both addresses security concerns, and is expected to greatly reduce the maintenance burden of the fluentd-gcp image. I'd *really* like to get this into 1.6, so please prioritize this review if possible.
I tested this by running the default e2e suite on a private e2e cluster using the new image. If there are other tests you'd like me to run, please let me know ASAP.
**Release note**:
```release-note
Cleanup fluentd-gcp image: rebase on debian-base, switch to upstream packages, remove fluent-ui & rails
```