annotate test files for secrets

[juli1]

What problem are you trying to solve?

We want to detect when a secret is detected in a test file.

What is your solution?

Run the same file classification for secrets than static analysis. When a result is found, we attempt to detect if this is a test file or not. If yes, we add the test classification that is later added to the SARIF file.

Testing

Added integration/end to end tests in misc/integration-test-secrets.sh

[datadog-datadog-prod-us1]

Datadog Summary

✅ Code Quality    ✅ Code Security    ✅ Dependencies

[Copilot]

Pull Request Overview

This PR aims to improve secret detection in test files by refining file classification logic.

• Introduces a new function get_language_for_file that determines the language based on file extension, exact filename, or prefix.
• Adds integration tests to verify this classification logic.
• Updates a comment for a minor spelling correction.

Files not reviewed (1)

• misc/integration-test-secrets.sh: Language not supported

Comments suppressed due to low confidence (2)

crates/cli/src/file_utils.rs:85

• [nitpick] Consider renaming 'extensions_string' to 'extension_strings' to more clearly indicate that it represents a collection of extension strings.

let extensions_string = extensions

crates/cli/src/file_utils.rs:109

• [nitpick] Consider renaming 'prefix_string' to 'prefix_strings' to reflect that it contains multiple items.

let prefix_string = prefixes