Deduplicate instantiate ServerDiagnostics and ServerCapabilities in case a full NS0 has added these.
Deduplicate instantiate ServerDiagnostics and ServerCapabilities in case a full NS0 has added these.

bostjanv/open62541,open62541/open62541,open62541/open62541,jpfr/open62541,StalderT/open62541,open62541/open62541,jpfr/open62541,JGrothoff/open62541,bostjanv/open62541,jpfr/open62541,AGIsmail/open62541,jpfr/open62541,StalderT/open62541,StalderT/open62541,JGrothoff/open62541,StalderT/open62541,JGrothoff/open62541,JGrothoff/open62541,open62541/open62541,AGIsmail/open62541