[ecr] [request]: Submit OCI conformance results against distribution-spec v1.0

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**Tell us about your request**
I would like assurance from Amazon that ECR is conformant against the [OCI distribution-spec](https://github.com/opencontainers/distribution-spec) v1.0.

This can be done by running the OCI conformance suite, and submitting a one-time PR against the [oci-conformance](https://github.com/opencontainers/oci-conformance) repo. Here are some [example PRs](https://github.com/opencontainers/oci-conformance/pulls?q=is%3Apr+%22Conformance+results+for+distribution-spec%2Fv1.0%22+) you can use for reference. The official instructions can be found [here](https://github.com/opencontainers/oci-conformance/blob/main/instructions.md).

**Which service(s) is this request for?**
ECR

**Tell us about the problem you're trying to solve. What are you trying to do, and why is it hard?**
N/A

**Are you currently working around this issue?**
N/A

**Additional context**
It is my understanding that ECR is already 100% OCI-conformant. This request is simply to ask that Amazon submit a PR to confirm this.

**Attachments**
The following may be useful:

- GitHub Actions YAML used previously to test ECR's conformance:
- [Pull](https://github.com/bloodorangeio/oci-conformance/blob/github-actions-save/.github/workflows/ecr_1.yml)
- [Push](https://github.com/bloodorangeio/oci-conformance/blob/github-actions-save/.github/workflows/ecr_2.yml)
- [Content Discovery](https://github.com/bloodorangeio/oci-conformance/blob/github-actions-save/.github/workflows/ecr_3.yml)
- [Content management](https://github.com/bloodorangeio/oci-conformance/blob/github-actions-save/.github/workflows/ecr_4.yml)
- [Instructions for how to run the OCI Conformance test suite](https://github.com/opencontainers/distribution-spec/blob/main/conformance/README.md)
- [OCI-Conformant Products webpage](https://conformance.opencontainers.org/), which ECR will appear on once results are submitted

Start with the OCI distribution-spec conformance README and the official oci-conformance instructions.md, then review the linked example pull requests and the referenced GitHub Actions workflows for ECR pull, push, content discovery, and content management. Run the distribution-spec v1.0 conformance suite against ECR and submit the one-time results PR to the oci-conformance repository.

Written by the indexing model from the issue text.