refactor: remove relative imports to selectors/index.js from other selectors files (#27642)

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Author: davidmurdoch

ui/selectors/multichain.ts

@@ -36,7 +36,7 @@ import {
   getSelectedInternalAccount,
   getShouldShowFiat,
   getShowFiatInTestnets,
-} from '.';
+} from './selectors';
 
 export type RatesState = {
   metamask: RatesControllerState;

ui/selectors/permissions.js

@@ -12,7 +12,7 @@ import {
   getOriginOfCurrentTab,
   getSelectedInternalAccount,
   getTargetSubjectMetadata,
-} from '.';
+} from './selectors';
 
 // selectors