Add board autodetection on upload

[silvanocerza]

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• Tests for the changes have been added (for bug fixes / features)
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• UPGRADING.md has been updated with a migration guide (for breaking changes)

• What kind of change does this PR introduce?

Adds a new feature.

• What is the current behavior?

The user must always provide an FQBN when trying to upload either with the compile or upload commands.

Example:

• arduino-cli upload -p /dev/ttyACM1 -b arduino:avr:uno

• arduino-cli compile -u -p /dev/ttyACM1 -b arduino:avr:uno

• What is the new behavior?

The user can now upload to a port without specifying an FQBN, if there is no ambiguity in the list of detected boards by the discoveries the commands will be successful. If the arduino-cli can't understand with 100% certainty which board is connected to the specified port the commands will exit with an error and let the user know that an FQBN must be provided.

Example commands:

• arduino-cli upload -p /dev/ttyACM1
• arduino-cli compile -u -p /dev/ttyACM1

Successful detection:

~/workspace/arduino-cli
$ arduino-cli board list
Port         Protocol Type              Board Name                FQBN             Core       
/dev/ttyACM0 serial   Unknown                                                     
/dev/ttyACM1 serial   Serial Port (USB) Arduino Mega or Mega 2560 arduino:avr:mega arduino:avr


~/workspace/arduino-cli
$ arduino-cli compile -u -p /dev/ttyACM1 ~/Arduino/Blink 
Sketch uses 1536 bytes (0%) of program storage space. Maximum is 253952 bytes.
Global variables use 9 bytes (0%) of dynamic memory, leaving 8183 bytes for local variables. Maximum is 8192 bytes.

~/workspace/arduino-cli
$ arduino-cli board list                                 
Port         Protocol Type              Board Name                FQBN             Core       
/dev/ttyACM0 serial   Unknown                                                     
/dev/ttyACM1 serial   Serial Port (USB) Arduino Mega or Mega 2560 arduino:avr:mega arduino:avr


~/workspace/arduino-cli
$ arduino-cli upload -p /dev/ttyACM1 ~/Arduino/Blink

In case multiple boards are detected an error is returned telling the user to specify the FQBN:

~/workspace/arduino-cli
$ arduino-cli board list
Port         Protocol Type              Board Name                FQBN                              Core                        
/dev/ttyACM0 serial   Unknown                                                                      
/dev/ttyACM1 serial   Serial Port (USB) Arduino Mega or Mega 2560 arduino-beta-development:avr:mega arduino-beta-development:avr
                      Serial Port (USB) Arduino Mega or Mega 2560 arduino:avr:mega                  arduino:avr                 


~/workspace/arduino-cli
$ arduino-cli compile -u -p /dev/ttyACM1 ~/Arduino/Blink 
Error during FQBN detection: Please specify an FQBN. Multiple possible ports detected on port /dev/ttyACM1 with protocol serial

~/workspace/arduino-cli
$ arduino-cli board list                            
Port         Protocol Type              Board Name                FQBN                              Core                        
/dev/ttyACM0 serial   Unknown                                                                      
/dev/ttyACM1 serial   Serial Port (USB) Arduino Mega or Mega 2560 arduino-beta-development:avr:mega arduino-beta-development:avr
                      Serial Port (USB) Arduino Mega or Mega 2560 arduino:avr:mega                  arduino:avr                 


~/workspace/arduino-cli
$ arduino-cli upload -p /dev/ttyACM1 ~/Arduino/Blink
Error during Upload: Please specify an FQBN. Multiple possible ports detected on port /dev/ttyACM1 with protocol serial

This also affects the gRPC consumers.

• Does this PR introduce a breaking change, and is
  titled accordingly?

Nope.

• Other information:

New fields have been added to existing gRPC messages so consumers will need to regenerate the source files from the .proto but there is no breaking change.

Closes #1357.

To test this you'll have to connect a board to your PC and run the test_upload.py integration tests since upload tests are not run on CI.

---

See how to contribute

[umbynos]

Also if you try to compile without uploading (-u) and without specifying the fqbn the cli returns an errror message different than before:
Error during FQBN detection: Missing port protocol new
Error during build: Missing FQBN (Fully Qualified Board Name) old

[ubidefeo]

@silvanocerza @umbynos
this doesn't work for me

I have a Nano 33 IoT attached to my machine.
It is successfully discovered by arduino-cli board list but when running

$> arduino-cli compile -u -p /dev/cu.usbmodem101
Error during FQBN detection: Missing FQBN (Fully Qualified Board Name)