Checkmk Werk 15489: Fix error message if limit for combined graphs is exceeded

ID: 15489 Title: Fix error message if limit for combined graphs is exceeded Component: metrics Level: 1 Class: Bug fix Version: 2.1.0p28 If the object or metric limit of a combined graph was reached, an error like "Problem while rendering dashboard element 4 of type combined_graph: Failed to calculate a graph recipe." was shown. You will now only see the information that a limit was reached.