revert: revert some unnecessary changes

Author: farhan

src/course-unit/add-component/AddComponent.tsx

@@ -187,7 +187,7 @@ const AddComponent = ({
             /* istanbul ignore next */
             ({ courseKey, locator }) => {
               setCourseId(courseKey);
-              setBlockType(moduleName ?? null);
+              setBlockType(moduleName);
               setNewBlockId(locator);
               showXBlockEditorModal();
             },

src/textbooks/Textbooks.tsx

@@ -14,7 +14,7 @@ import { SavingErrorAlert } from '@src/generic/saving-error-alert';
 import { LoadingSpinner } from '@src/generic/Loading';
 import SubHeader from '@src/generic/sub-header/SubHeader';
 
-import ConnectionErrorAlert from '../generic/ConnectionErrorAlert';
+import ConnectionErrorAlert from '@src/generic/ConnectionErrorAlert';
 import EmptyPlaceholder from './empty-placeholder/EmptyPlaceholder';
 import TextbookCard from './textbook-card/TextbooksCard';
 import TextbookSidebar from './textbook-sidebar/TextbookSidebar';