Add lookaside to traverse - Limits DFS revisit

[dballance]

Description

See #1150. Adds a 'per-patch' lookaside to the traverse method within createKeyBasedPlugin.

Motivation and Context

Previously, a $ref would be traversed multiple times during spec resolution. This change allows $refs to be resolved once and prevents future unnecessary revisits.

Fixes #1150 - but still some questions about handling allOf resolution that may be handled in another PR.

How Has This Been Tested?

All tests appear to pass - unsure if additional tests are required or need to be added for this change.

Existing code. Small spec (~5k lines formatted JSON). Average Resolution of ~1100ms.

With change. Average Resolution of ~250ms.

Existing code. Large spec (~141k lines formatted JSON). NOTE: allOf plugin disabled for the below tests - only running $ref plugin.
???? I couldn't actually get this to complete in any reasonable time. 😄

With change. Average Resolution of ~5200ms.

Types of changes

• No code changes (changes to documentation, CI, metadata, etc)
• Dependency changes (any modification to dependencies in package.json)
• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)

Checklist:

• My code follows the code style of this project.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have added tests to cover my changes.
• All new and existing tests passed.

[shockey]

Thanks for this, @dballance! Very excited to ship this, I expect significant gains across the board for large definitions 😄