Add initially stubbed ocicatalog grpc service.

[absoludity]

Description of the change

As per #6263, this PR adds an initally stubbed ocicatalog service gRPC service implementation.

Benefits

Can begin building the fully featured OCI Catalog for indexing OCI repositories.

Applicable issues

• Ref Implementation of OCI-Catalog gRPC micro-service #6263

Additional information

$ grpcurl -proto ./proto/ocicatalog.proto -d '{"registry": "registry-1.docker.io"}' -plaintext "[::1]:50051" ocicatalog.OCICatalog.ListRepositoriesForRegistry
{
  "registry": "registry-1.docker.io",
  "name": "repo-0"
}
{
  "registry": "registry-1.docker.io",
  "name": "repo-1"
}
{
  "registry": "registry-1.docker.io",
  "name": "repo-2"
}
{
  "registry": "registry-1.docker.io",
  "name": "repo-3"
}
{
  "registry": "registry-1.docker.io",
  "name": "repo-4"
}
{
  "registry": "registry-1.docker.io",
  "name": "repo-5"
}
{
  "registry": "registry-1.docker.io",
  "name": "repo-6"
}
{
  "registry": "registry-1.docker.io",
  "name": "repo-7"
}
{
  "registry": "registry-1.docker.io",
  "name": "repo-8"
}
{
  "registry": "registry-1.docker.io",
  "name": "repo-9"
}

$ grpcurl -proto ./proto/ocicatalog.proto -d '{"repository": {"registry": "registry-1.docker.io"}}' -plaintext "[::1]:50051" ocicatalog.OCICatalog.ListTagsForRepository
{
  "name": "tag-0"
}
{
  "name": "tag-1"
}
{
  "name": "tag-2"
}
{
  "name": "tag-3"
}
{
  "name": "tag-4"
}
{
  "name": "tag-5"
}
{
  "name": "tag-6"
}
{
  "name": "tag-7"
}
{
  "name": "tag-8"
}
{
  "name": "tag-9"
}

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[github-actions]

license-eye has totally checked 1634 files.

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805	2	827	0

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• cmd/oci-catalog/Cargo.toml
• cmd/oci-catalog/build.rs

[github-actions]

Suggested change

	[package]
	# Copyright 2023 the Kubeapps contributors
	#
	# Licensed under the Apache License, Version 2.0 (the "License");
	# you may not use this file except in compliance with the License.
	# You may obtain a copy of the License at
	#
	# http://www.apache.org/licenses/LICENSE-2.0
	#
	# Unless required by applicable law or agreed to in writing, software
	# distributed under the License is distributed on an "AS IS" BASIS,
	# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
	# See the License for the specific language governing permissions and
	# limitations under the License.
	[package]

[github-actions]

Suggested change

	fn main() -> Result<(), Box<dyn std::error::Error>> {
	// Copyright 2023 the Kubeapps contributors
	//
	// Licensed under the Apache License, Version 2.0 (the "License");
	// you may not use this file except in compliance with the License.
	// You may obtain a copy of the License at
	//
	// http://www.apache.org/licenses/LICENSE-2.0
	//
	// Unless required by applicable law or agreed to in writing, software
	// distributed under the License is distributed on an "AS IS" BASIS,
	// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
	// See the License for the specific language governing permissions and
	// limitations under the License.
	fn main() -> Result<(), Box<dyn std::error::Error>> {