[hotfix] Fix docker file build exception

[luoyuxia]

Purpose

Fix the exception when build with docker image:

Step 3/12 : COPY --chown=fluss:fluss build-target/ /opt/fluss/
unable to convert uid/gid chown string to host mapping: can't find uid for user fluss: no such user: fluss

NOTE: Seems It only happens with colima, the offical docker still work

Brief change log

Create the user firstly.

Tests

API and Format

Documentation

[Copilot]

Pull Request Overview

This hotfix addresses a Docker build exception where the COPY --chown=fluss:fluss command fails because the fluss user doesn't exist at that point in the build process.

• Moves user and group creation before the COPY command that requires the user
• Fixes the Docker build process by ensuring proper command ordering

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