Not specifying fee rate (ppm) in the Change (All) Channel Details dialog forces fee rate to 1 on submission

[initfortherekt]

Describe the problem/bug Not specifying a fee rate on the Change Channel Details dialog will cause all channel fee rates to be set to a value of 1

Your environment

• Version of ThunderHub: 0.12.21
• Deployment method: local

To Reproduce Steps to reproduce the behavior:

Go to Channels
Click on the Gear Icon
Click the 'Change' button to the right of "Change Channel Details"
Specify a base fee and DO NOT specify a fee rate
Click the 'Update All Channels' button

Expected behavior If no fee rate is specified, it should not affect any channel's fee rate -- OR -- A sensible fee rate value is defaulted in the form input and the user is warned when they change or clear it

Actual behavior Fee rates are set to 1ppm on all channels

[mutatrum]

The reverse case is also true: specify a fee rate and leave base fee empty will set base fee to 1 on all channels.

ThunderHub 0.13.6