docs(docker-readme): format and fix code blocks to prevent warnings

[akrem-chabchoub]

Checklist

• I have read the coding guide.
• My change requires a documentation update, and I have done it.
• I have added tests to cover my changes.
• I have filled out the description and linked the related issues.

Description

Fix docker readme mardown issues by:

• Adding bash and yaml language identifiers to code blocks
• Adding blank lines before and after fenced code blocks
• Adding blank lines around list items and headings

Open API Spec Version Changes (if applicable)

Motivation and Context (Optional)

Related Issue (Optional)

#5272

Screenshots (if appropriate):

Before the changes:

[Copilot]

Pull Request Overview

This PR enhances the documentation formatting in the Docker README by adding language specifiers to code blocks and improving readability with additional blank lines. The changes make the documentation more accessible and enable proper syntax highlighting.

Key changes:

• Added language identifiers (bash, yaml) to all code blocks for syntax highlighting
• Inserted blank lines before code blocks to improve visual separation and readability

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