Remove local underscore import

[caseycesari]

Overview

Issues referencing underscore in plugins was remedied in CoastalResilienceNetwork/GeositeFramework#669. Local imports of underscore are no longer needed and cause conflicts with the framework version of underscore when they exist.

Testing

• Bring up an instance of the framework on develop, and add this plugin.
• Ensure the plugin loads and layers can be added.

[jwalgran]

Reviewing this now

[caseycesari]

Thanks

[jwalgran]

I replace my previous regional-planning plugin with this branch and was still able to load layers

[caseycesari]

Thanks!