If install script installs a tag/branch/commit, pin workflows to that

[dwhswenson]

Previously, the install script was just downloading the examples as of that commit. Now we pin usage to that as well.

[github-actions]

This PR has been staged at https://f5d6677a.astro-site-testing.pages.dev.

It has been updated for commit e363674.

[Copilot]

Pull Request Overview

The PR enhances the install script to pin workflow references to the specified tag, branch, or commit being installed, ensuring consistency between the downloaded examples and their reusable workflow references.

• Adds a new function update_reusable_workflow_references to pin workflow references after downloading
• Updates the integration test to verify that workflow references are properly pinned
• Improves shell script quoting and adds validation for pinned references

Reviewed Changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 2 comments.

File	Description
install.py	Adds workflow reference pinning functionality and integrates it into the install process
test_install.py	Adds comprehensive tests for the new pinning functionality and updates existing tests
test_install.sh	Improves shell script with proper quoting and adds validation for pinned workflow references

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[github-actions]

This PR has been staged at https://4fa535a4.static-site-tools-testing.pages.dev.

It has been updated for commit e363674.

[github-actions]

This PR has been staged at https://608f6a8f.jekyll-site-testing.pages.dev.

It has been updated for commit e363674.