Add Dockerfile and docs for building Cloudberry Docker Images

[tuhaihe]

Fixes #ISSUE_Number

What does this PR do?

Type of Change

• Bug fix (non-breaking change)
• New feature (non-breaking change)
• Breaking change (fix or feature with breaking changes)
• Documentation update

Breaking Changes

Test Plan

• Unit tests added/updated
• Integration tests added/updated
• Passed make installcheck
• Passed make -C src/test installcheck-cbdb-parallel

Impact

Performance:

User-facing changes:

Dependencies:

Checklist

• Followed contribution guide
• Added/updated documentation
• Reviewed code for security implications
• Requested review from cloudberry committers

Additional Context

CI Skip Instructions

---

[tuhaihe]

Try:

docker build -f devops/build/packaging/docker/Dockerfile.rocky9 -t apache/cloudberry:2.1 .

docker run --rm -it \                         1 ↵
  -d \
  --name cloudberry-db \
  -e POSTGRES_HOST_AUTH_METHOD=trust \
  -p 5432:5432 \
  apache/cloudberry:2.1

docker exec -it cloudberry-db bash -lc "source /usr/local/cloudberry-db/cloudberry-env.sh && psql -d postgres"