Automatically detect/update if local gateway port changes in config

**Describe the bug**
when ipfs local gateway changes the port 8080 to 8081 then FF ipfs companion does not change port 8080 to 8081

**To Reproduce**
Steps to reproduce the behavior:
1. launch vlc using port 8080 for remote control
2. launch ipfs-desktop
3. ipfs-desktop offers to change to 8081
4. i accept
5 i launch FF then i click on ipfs companion
6. i see that local gateway port is still 8080
7.
**Expected behavior**
in ipfs companion local gateway port automatically changes to 8081

**Desktop (please complete the following information):**
- openSuse 15.2
- Firefox 84.0.2, ipfs companion 2.17.2
- snap packet ipfs-desktop 0.13.2