Add support for checking out non-existent branches in JUnit reports workflow

[Donnerbart]

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[Copilot]

Pull Request Overview

This PR adds support for gracefully handling non-existent branches in the JUnit reports workflow, allowing the action to continue on the default branch instead of failing.

• Adds logic to check if a target branch exists before attempting to checkout
• Implements fallback behavior to stay on the default branch when the target branch doesn't exist
• Adds integration test to verify the new non-existent branch handling functionality

Reviewed Changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 4 comments.

File	Description
checkout-junit-reports/action.yml	Adds branch existence checks and fallback logic for non-existent branches
.github/workflows/integration-test.yml	Adds test case to verify non-existent branch handling behavior

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[Copilot]

Pull Request Overview

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

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_{Tip: Customize your code reviews with copilot-instructions.md. Create the file or learn how to get started.}

[Copilot]

Pull Request Overview

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

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_{Tip: Customize your code reviews with copilot-instructions.md. Create the file or learn how to get started.}