fix(compiler): merge user plugins with default plugins

Author: lokesh-coder

packages/compiler/src/index.ts

@@ -88,7 +88,7 @@ class LesyCompiler {
  if (this.opts.loadDefaultPlugins) {
  appData.plugins = [
  ...this.defaultPlugins.map((p: string) => require.resolve(p)),
- ...appData.plugins,
+ ...(appData.plugins || []),
  ];
  }
  const config = this.defaultConfig;