Ignore node_modules in the packages

[maxjeffos]

• Ready for review
• Follows CONTRIBUTING rules
• Reviewed by Snyk internal team

What does this PR do?

Ignore node_modules folders in the root of a package (/packages/<package-name>/node_modules). This will NOT ignore other node_modules such as those used in test fixtures (ex /packages/<package-name>/test/fixtures...)

Any background context you want to provide?

The node_modules generated by npm install in the root of the new snyk-fix package is not being ignored.

[github-actions]

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📖	This PR will not trigger a new version. It doesn't include any commit message with feat or fix.

Generated by 🚫 dangerJS against 6897a45

[ghost]

To better represent intent here, it might be worth ignoring all node_modules and then adding an exception for fixtures. But this isn't blocking, just an idea, as ignoring all node_modules is generally considered default behaviour.