PR-733704: use transpileOnly in webpack.cy.config.ts ts-loader

Cypress only needs transpilation, not full type-checking. This removes
TS2307 (@storybook/react-webpack5 types) and TS2339 (toBeInTheDocument)
errors from the Cypress webpack build output.

webpack.cy.config.ts

@@ -48,7 +48,10 @@ export default {
 			{
 				test: /\.(ts|tsx)$/,
 				exclude: /node_modules/,
-				use: 'ts-loader',
+				use: {
+				loader: 'ts-loader',
+				options: { transpileOnly: true },
+			},
 		  },
 		  {
 				test: /\.(js|jsx)$/,