message: Ensure esbuild config is deep copied
diff: @@ -264,7 +264,9 @@ export function builder(builderProps: BuilderProps): BuilderOutput {
  // Get custom esbuild config
  bundle = bundle as FunctionBundleNodejsProps;
  - let customConfig = appEsbuildConfig || bundle.esbuildConfig || {};
  +
  + // We need to deep clone so we don't run into mutation issues
  + let customConfig = JSON.parse(JSON.stringify(appEsbuildConfig || bundle.esbuildConfig || {}));
  // note: "esbuildConfig" used to take a string, a path to the user
  // provided config file. With the new format, esbuildConfig is
  // configured inline, and the external file can only be used
  