Apply CNCF convention on attributions

[gbartolini]

Given that now CNPG is officially a CNCF project we must update the attribution information for contributions to the project by following the CNCF convention on attributions:

#
# Copyright © contributors to CloudNativePG, established as
# CloudNativePG a Series of LF Projects, LLC.
#
# 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.
#
# SPDX-License-Identifier: Apache-2.0
#

[itay-grudev]

@gbartolini Quick question. There are two ways we can apply these.

1. They will be visible in every Kubernetes YAML resource as a YAML comment # comment
2. They will be visible only in the Helm templates as a gotmpl comment sequence {{- /* comment */}}

Option 1 will pollute and bloat the output.

[dosubot]

Hi, @gbartolini. I'm Dosu, and I'm helping the charts team manage their backlog. I'm marking this issue as stale.

Issue Summary

• The issue involves updating attribution information to comply with CNCF conventions.
• This requires adding copyright and licensing notices to the project's files.
• @itay-grudev suggested two implementation options: direct comments in Kubernetes YAML or comments in Helm templates.

Next Steps

• Please confirm if this issue is still relevant to the latest version of the charts repository. If so, you can keep the discussion open by commenting here.
• If there is no further activity, the issue will be automatically closed in 7 days.

Thank you for your understanding and contribution!