[2.3.0] Checkmk Werk 14617 created: check_uniserv: running the active check results in exception "TypeError: a bytes-like object is required, not 'str'"

[//]: # (werk v2) # check_uniserv: running the active check results in exception "TypeError: a bytes-like object is required, not 'str'" key | value ---------- | --- date | 2024-01-17T15:06:16+00:00 version | 2.3.0b1 class | fix edition | cre component | checks level | 1 compatible | yes `check_uniserv` implementation didn't encode the `close` command resulting in an exception `TypeError: a bytes-like object is required, not 'str'` being raised. This change adds the missing encoding among some general modernization.