fix nonce error with remix dev server (#774)

Author: zwhitchcox

app/entry.server.tsx

@@ -44,7 +44,7 @@ export default async function handleRequest(...args: DocRequestArgs) {
 		? 'onAllReady'
 		: 'onShellReady'
 
-	const nonce = String(loadContext.cspNonce) ?? undefined
+	const nonce = loadContext.cspNonce?.toString() ?? ''
 	return new Promise(async (resolve, reject) => {
 		let didError = false
 		// NOTE: this timing will only include things that are rendered in the shell