DXCDT-374: Update field by address for keyword preservation

[willvedd]

🔧 Changes

Building off of the previous PRs for keyword preservation (#736, #738, #740, #741), this PR adds the updateAssetsByAddress function which will update a field on an arbitrary data structure when provided the address and the new value. This functionality is critical for keyword preservation because ultimately this is what will replace certain fields on the remote assets tree with the preserved fields of the local asset tree.

Example:

updateAssetsByAddress(
  { tenant: { friendly_name: 'Original friendly name' } },
  'tenant.friendly_name',
  'New friendly name'
); // { tenant: { friendly_name: 'New friendly name' } },

📚 References
Related Issues:

• Preserve keyword replacement during export #328
• Proposal: Keyword Preservation During Export #688

🔬 Testing
Added and updated unit tests.

📝 Checklist

• All new/changed/fixed functionality is covered by tests (or N/A)
• I have added documentation for all new/changed functionality (or N/A)