chore(plugin-vue): simplify resolved declaration

Co-authored-by: edison <[email protected]>

Author: Aaron-zon

Diff for: packages/plugin-vue/src/script.ts

@@ -69,9 +69,7 @@ export function resolveScript(
     return cached
   }
 
-  let resolved: SFCScriptBlock | null = null
-
-  resolved = options.compiler.compileScript(descriptor, {
+  const resolved: SFCScriptBlock = options.compiler.compileScript(descriptor, {
     ...options.script,
     id: descriptor.id,
     isProd: options.isProduction,