Describe the problem

When installing the mbed_portenta core, an error message is displated regarding the ESP8266 having malformed custom board options. Does not noticablely affect the operation with a Portenta board otherwise.

To reproduce

1. Open Windows PowerShell (non-adminsistrator)
2. Provide permissions for the Scoop installer Set-ExecutionPolicy -ExecutionPolicy RemoteSigned -Scope CurrentUser
3. Install the latest arduino IDE via scoop scoop install arduino-cli (in this case, 0.27.0)
4. Update the CLI index then install the mbed_portenta core arduino-cli core install arduino:mbed_portenta
5. The following message is displayed

Downloading missing tool builtin:mdns-discovery@1.0.6...
builtin:mdns-discovery@1.0.6 downloaded
Installing builtin:mdns-discovery@1.0.6...
builtin:mdns-discovery@1.0.6 installed
Error initializing instance: Error loading hardware platform: loading platform release esp8266:esp8266@2.7.1: loading boards: skipping loading of boards esp8266:esp8266:espduino: malformed custom board options
Error initializing instance: Error loading hardware platform: loading platform release esp8266:esp8266@2.7.1: loading boards: skipping loading of boards esp8266:esp8266:espduino: malformed custom board options

Expected behavior

No messages about the ESP8266 would show up.

Arduino CLI version

0.27.0

Operating system

Windows

Operating system version

Windows 10

Additional context

No response

Issue checklist

• I searched for previous reports in the issue tracker
• I verified the problem still occurs when using the nightly build
• My report contains all necessary details