Allow resizing left/right sidebars

[SpendeskArtemis]

Please answer the questions below, it helps us to track the issue.

1. Database version (Ex: PostgreSQL 10.0): not relevant

2. TablePlus version (the number on the welcome or about screen, Ex: build 81): 0.1.192

3. Linux distro (Ex: Ubuntu 18.04): ArchLinux

4. The steps to reproduce this issue: Open the software, connect to a DB

Noted: If the bug is related to data, please attach an example SQL data.

The sidebars currently have a fixed size; It'd be good to allow resizing them with the mouse or keyboard.

[huyphams]

I'm not sure that I understand you correctly, you mean the database sidebar or item sidebar?