next-codemod(upgrade): optional catch when missing dev script (#71598)

### Why?

During the next-codemod upgrade, when the `dev` script is missing, it
throws while reading `.includes` the undefined value.

Fixes #71597

---------

Co-authored-by: Jiwon Choi <devjiwonchoi@gmail.com>

packages/next-codemod/bin/upgrade.ts

@@ -412,7 +412,7 @@ function isUsingAppDir(projectPath: string): boolean {
  */
 async function suggestTurbopack(packageJson: any): Promise<void> {
   const devScript: string = packageJson.scripts['dev']
-  if (devScript.includes('--turbopack')) return
+  if (devScript?.includes('--turbopack')) return
 
   const responseTurbopack = await prompts(
     {