Updated linux script install to use pip

[mikefrobbins]

PR Summary

Fixes AB#496623, Fixes #5533 - Updated linux script install article to use pip.

PR Checklist

• Descriptive Title: This PR's title is a synopsis of the changes it proposes.
• Summary: This PR's summary describes the scope and intent of the change.

[Copilot]

Pull Request Overview

This PR updates the Linux script installation documentation to use pip with a virtual environment instead of the legacy installation script. This change aligns with modern Python packaging best practices and simplifies the installation process.

• Replaces the legacy curl | bash installation script with pip-based installation in a Python virtual environment
• Updates requirements to specify Python 3.8 or higher instead of specific versions
• Modernizes troubleshooting steps to reflect the new pip-based installation method

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[learn-build-service-prod]

Learn Build status updates of commit a96e86f:

✅ Validation status: passed

File	Status	Preview URL	Details
docs-ref-conceptual/Latest-version/includes/cli-install-linux-script.md	✅Succeeded	View (azure-cli-latest)

For more details, please refer to the build report.

[learn-build-service-prod]

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[learn-build-service-prod]

Learn Build status updates of commit a2f3cdd:

✅ Validation status: passed

File	Status	Preview URL	Details
docs-ref-conceptual/Latest-version/includes/cli-install-linux-script.md	✅Succeeded	View (azure-cli-latest)

For more details, please refer to the build report.