feat: add building option to build images base on distroless image

[WaterWhisperer]

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Refer to a related PR or issue link (optional)

#2115

What's changed and what's your intention?

support building option to build images base on distroless image and fix some warning in existing Dockerfile to remove noise

PR Checklist

Please convert it to a draft if some of the following conditions are not met.

• I have written the necessary rustdoc comments.
• I have added the necessary unit tests and integration tests.
• This PR requires documentation updates.
• API changes are backward compatible.
• Schema or data changes are backward compatible.

[killme2008]

Thanks.

@sunng87 @lyang24 Please take a look.

[Copilot]

Pull Request Overview

This PR adds support for building GreptimeDB Docker images based on distroless images for enhanced security and smaller image size, while also fixing Docker best practice warnings in existing Dockerfiles.

• Adds two new distroless Dockerfile variants (ci and buildx)
• Standardizes ENV variable syntax across all Dockerfiles (removes spaces around =)
• Capitalizes AS keyword in multi-stage builds to follow Docker best practices

Reviewed Changes

Copilot reviewed 6 out of 6 changed files in this pull request and generated 5 comments.

Show a summary per file

File	Description
docker/ci/distroless/Dockerfile	New distroless-based image for CI builds
docker/buildx/distroless/Dockerfile	New distroless-based image with build-from-source support
docker/ci/ubuntu/Dockerfile	Fixed ENV syntax warning
docker/ci/centos/Dockerfile	Fixed ENV syntax warning
docker/buildx/ubuntu/Dockerfile	Fixed ENV syntax and capitalized AS keyword
docker/buildx/centos/Dockerfile	Fixed ENV syntax and capitalized AS keyword

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[lyang24]

lgtm can you also add info to the docs repo?
like https://github.com/GreptimeTeam/docs/blob/9f492d9c42a47bb519cc70b5a2b1a4f3367271a7/docs/getting-started/installation/greptimedb-standalone.md?plain=1#L71

[sunng87]

@WaterWhisperer Just one more concern with the duplicates in ubuntu version and distroless version. Do you think we should switch completely from ubuntu to distroless? Is there any impact?

@daviderli614 what's your ideas about this?

[WaterWhisperer]

@WaterWhisperer Just one more concern with the duplicates in ubuntu version and distroless version. Do you think we should switch completely from ubuntu to distroless? Is there any impact?

@daviderli614 what's your ideas about this?

I'd recommend keeping both as options rather than switching completely. Ubuntu is easier debugging and Distroless is smaller, more secure.
Users can choose via BASE_IMAGE variable (ubuntu is default). No breaking changes.

[WaterWhisperer]

lgtm can you also add info to the docs repo? like https://github.com/GreptimeTeam/docs/blob/9f492d9c42a47bb519cc70b5a2b1a4f3367271a7/docs/getting-started/installation/greptimedb-standalone.md?plain=1#L71

Okay, I'd like to work on #2217 when this PR doesn't need any changes