Update Specs for NPM 8 as Default and Fallback Version

[kbukum1]

What are you trying to accomplish?

This PR updates test specs to align with the recent changes introduced in the merged PR Update NPM Default and Fallback Versions to NPM 8. These changes ensure that all specs accurately reflect the new default and fallback npm version of 8.

These updates address test mismatches in registry URL and npm version handling following the update to npm 8 as the fallback version.

Anything you want to highlight for special attention from reviewers?

This update ensures compatibility with npm 8 as the standard for dependency resolution, while maintaining legacy npm 6 behavior where necessary. The npm_fallback_version_above_v6 feature flag is enabled or disabled in specs based on the specific scenario being tested.

How will you know you've accomplished your goal?

• Testing: All tests should pass with npm 8 as the default and fallback version.
• Validation: Specs should reflect the correct npm version and registry URL under all test conditions.

Checklist

• I have run the complete test suite to ensure all tests and linters pass.
• I have thoroughly tested my code changes to ensure they work as expected, including additional tests for flag-enabled functionality.
• I have written clear and descriptive commit messages.
• I have provided a detailed description of the changes in the pull request, including the problem it addresses, how it fixes the problem, and any relevant details about the implementation.
• I have ensured that the code is well-documented and easy to understand.