Allow configuring secure channel lifetime instead of hardcoded value (1 minute)

[jonasar]

The requested secure channel lifetime is hardcoded as 60 seconds in function issue_or_renew_secure_channel() in session_state.rs.

This is a request to add this as a parameter to the client builder instead.

I am using version 0.8.1 of the opcua library, but I see that this is still hardcoded in the latest commit on master.

[jonasar]

This short hardcoded secure channel lifetime makes https://github.com/locka99/opcua/issues/207 much worse since the connection is lost approximately every 3rd time (in my case, connecting to the OPC UA server in a Siemens Siematic S7-1500) that the secure channel token is renewed.