Checkmk Werk 11906: Improve message length computation in fetcher protocol

ID: 11906 Title: Improve message length computation in fetcher protocol Component: Core & setup Level: 1 Class: Bug fix Version: 2.1.0i1 The computation of the length of SNMP payloads is now consistent with improperly escaped JSON strings. Previously, the inconsistency could result in the crash of the SNMP checks.