message: fix(feature-flags): corrected docs to instantiate FeatureFlags
diff: @@ -35,7 +35,7 @@ import {
  } from '@backstage/core';
  const builder = ApiRegistry.builder();
  -builder.add(featureFlagsApiRef, FeatureFlags);
  +builder.add(featureFlagsApiRef, new FeatureFlags());
  export default builder.build() as ApiHolder;
  ```
  