[Actions] Add permissions to all workflows

[VeithMetro]

This is a fix for this code scanning alert

[Copilot]

Pull Request Overview

This PR addresses a security code scanning alert by adding explicit permission restrictions to GitHub Actions workflows. The changes implement the principle of least privilege by limiting workflow permissions to read-only access to repository contents.

Key Changes:

• Added explicit permissions: contents: read to all workflow files
• Standardizes security posture across MacOS, Linux, and Windows build workflows

Reviewed Changes

Copilot reviewed 5 out of 5 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
.github/workflows/MacOS build template.yml	Added read-only contents permission to MacOS build template
.github/workflows/Linux build template.yml	Added read-only contents permission to Linux build template
.github/workflows/Build ThunderNanoServicesRDK on Windows.yml	Added read-only contents permission to Windows build workflow
.github/workflows/Build ThunderNanoServicesRDK on MacOS.yml	Added read-only contents permission to MacOS build workflow
.github/workflows/Build ThunderNanoServicesRDK on Linux.yml	Added read-only contents permission to Linux build workflow

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