Remove types that didn't work well

Author: Ben Grynhaus

libs/core/src/lib/declarations/index-signature.d.ts

@@ -1,11 +1,6 @@
 // Copyright (c) Microsoft Corporation. All rights reserved.
 // Licensed under the MIT License.
 
-import { IndexSignature } from './index-signature';
 import { KnownKeys } from './known-keys';
-import { UnknownKeys } from './unknown-keys';
 
-export type _KnownKeysOmit<T, K extends keyof T> = Pick<T, Exclude<KnownKeys<T> & keyof T, K>>;
-export type Omit<T, K extends keyof T> = UnknownKeys<T> extends never
-  ? _KnownKeysOmit<T, K>
-  : _KnownKeysOmit<T, K> & IndexSignature<T>;
+export type Omit<T, K extends keyof T> = Pick<T, Exclude<KnownKeys<T> & keyof T, K>>;