fix: resolve library entry

Author: yyx990803

packages/vite/src/node/build.ts

@@ -289,7 +289,7 @@ async function doBuild(
 
   const resolve = (p: string) => path.resolve(config.root, p)
   const input = libOptions
-    ? libOptions.entry
+    ? resolve(libOptions.entry)
     : options.rollupOptions?.input || resolve('index.html')
 
   if (ssr && typeof input === 'string' && input.endsWith('.html')) {