[digiplex] Fix exception handling in sender and receiver threads

[rmichalak]

Improves error handling in sender and receiver threads so that the threads do not occasionally stop when an unexpected exception occurs.

Closes #17828

[jlaur]

Improves error handling in sender and receiver threads so that the threads do not occasionally stop when an unexpected exception occurs.

Which unexpected exception have you observed?

[rmichalak]

Improves error handling in sender and receiver threads so that the threads do not occasionally stop when an unexpected exception occurs.

Which unexpected exception have you observed?

Honestly, I don't remember now. I'm the original author of this binding and I had this fix applied in my environment for a long time (just forgot to push it to remote). As far as I remember, my alarm system is sending some rubbish over RS232 from time to time and then parsing may fail in many unexpected ways. that's why I have this handleCommunicationError function which reinitializes everything.