Small change in upload message

[cmaglie]

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What kind of change does this PR introduce?

Slightly changes an output message in upload

What is the current behavior?

The "no port found" upload message was:

No upload port found, using address:"/dev/ttyACM0"  protocol:"serial"  as fallback

(notice that the message contains double spaces that are produced pseudo-randomly when a structure is printed using the default String() implementation)

What is the new behavior?

Just print the port address:

No upload port found, using /dev/ttyACM0 as fallback

This is more user-friendly, and the message is 100% reproducible for testing purposes.

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

No