Postico 2: requires restart Invalid argument waiting for network connection

## What did you do?

- I ejected a current connection that had been open overnight
- Then I pressed connect on my local connection
- Quit postico
- Reopened postico
- connected again and it all worked fine.

## What did you expect to happen?

- I expected it to connect as normal

## What actually happened?

- It showed an error "Invalid argument waiting for network connection"

- it required killing and restarting postico 2

## What software versions are you using?

Postico version:
Version 2.0beta (6982)

macOS version:
10.15.6

PostgreSQL version:
PostgreSQL 10.11 on x86_64-apple-darwin14.5.0, compiled by Apple LLVM version 7.0.0 (clang-700.1.76), 64-bit

Reproduce the reported sequence in Postico 2 beta 6982 on macOS 10.15.6 with PostgreSQL 10.11: eject an overnight connection, reconnect, quit, and reopen. Investigate the connection path around ejection and reconnecting; done means the local connection succeeds without restarting Postico after the error.

Written by the indexing model from the issue text.