code: public IterableOfProtosFluentAssertion<M> usingDoubleToleranceForFieldDescriptors(
        double tolerance, FieldDescriptor firstFieldDescriptor, FieldDescriptor... rest) {
      return usingConfig(
          config.usingDoubleToleranceForFieldDescriptors(
              tolerance, asList(firstFieldDescriptor, rest)));
    }
docs: Compares double fields with these explicitly specified fields using the provided absolute
  tolerance.
  
  @param tolerance A finite, non-negative tolerance.