Use gRPC function call to avoid accessing arduino/cores package directly

[MatteoPologruto]

Please check if the PR fulfills these requirements

See how to contribute

• The PR has no duplicates (please search among the Pull Requests
  before creating one)
• The PR follows
  our contributing guidelines
• Tests for the changes have been added (for bug fixes / features)
• Docs have been added / updated (for bug fixes / features)
• UPGRADING.md has been updated with a migration guide (for breaking changes)
• configuration.schema.json updated if new parameters are added.

What kind of change does this PR introduce?

No changes, the code is reorganized to avoid accessing arduino/cores package directly.

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

No

Other information

Related to #1948

[codecov]

Codecov Report

Patch coverage: 100.00% and project coverage change: +0.04% 🎉

Comparison is base (3f9373a) 63.40% compared to head (e244d17) 63.45%.

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #2292      +/-   ##
==========================================
+ Coverage   63.40%   63.45%   +0.04%     
==========================================
  Files         219      219              
  Lines       19536    19538       +2     
==========================================
+ Hits        12386    12397      +11     
+ Misses       6069     6052      -17     
- Partials     1081     1089       +8     

Flag	Coverage Δ
unit	63.45% <100.00%> (+0.04%)	⬆️

Flags with carried forward coverage won't be shown. Click here to find out more.

Files Changed	Coverage Δ
internal/cli/arguments/completion.go	87.83% <100.00%> (+0.16%)	⬆️

... and 2 files with indirect coverage changes

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.