RTL doesn't work with Action Mapping

[Ari Beck]

angular-tree-component/projects/angular-tree-component/src/lib/models/tree-options.model.ts

Line 134 in 19b58ab

 this.actionMapping.keys[KEYS.RIGHT] = <IActionHandler>options.actionMapping?.keys[KEYS.RIGHT] || TREE_ACTIONS.DRILL_UP; 

keys is optional in the IActionMapping type but is required here in order to check if keys[KEYS.RIGHT] exists.