feat(examples): Use a token lifetime of 300s in server_ctt
feat(examples): Use a token lifetime of 300s in server_ctt

So we have more tokens revolving during the tests.
Better coverage to test that functionality.

jpfr/open62541,JGrothoff/open62541,jpfr/open62541,jpfr/open62541,open62541/open62541,JGrothoff/open62541,JGrothoff/open62541,jpfr/open62541,open62541/open62541,open62541/open62541,JGrothoff/open62541,open62541/open62541