Fix path in error messages on sketch loading

[cmaglie]

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• 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)

What kind of change does this PR introduce?

• Fix Incorrect error details when the LoadSketchRequest fails with NOT_FOUND error #1797
• Removes a compatibility layer for the Arduino IDE 1.x, see Added flag to disable check for sketch foldername matching sketch name #1187 for details. The proper fix must be made in the Arduino IDE 1.x, not as an exception in the CLI.

What is the current behavior?

$ arduino-cli version
arduino-cli.exe  Version: git-snapshot Commit: 6ac5f7a3 Date: 2022-07-09T19:16:18Z

$ mkdir /tmp/Arduino

$ arduino-cli compile -b arduino:avr:uno /tmp/Arduino/alma
Error opening sketch: no valid sketch found in C:\Users\per\AppData\Local\Temp\Arduino: missing C:\Users\per\AppData\Local\Temp\Arduino\Arduino.ino

$ arduino-cli compile -b arduino:avr:uno /tmp/Arduino/alma/alma.ino
Error opening sketch: reading files: open C:\Users\per\AppData\Local\Temp\Arduino\alma: The system cannot find the file specified.

$ arduino-cli compile -b arduino:avr:uno /tmp/Arduino/alma/nonexistent
Error opening sketch: reading files: open C:\Users\per\AppData\Local\Temp\Arduino\alma: The system cannot find the file specified.

What is the new behavior?

$ arduino-cli version
arduino-cli.exe  Version: git-snapshot Commit: 6ac5f7a3 Date: 2022-07-09T19:16:18Z

$ mkdir /tmp/Arduino

$ arduino-cli compile -b arduino:avr:uno /tmp/Arduino/alma
Error opening sketch: main file missing from sketch: /tmp/Arduino/alma/alma.ino

$ arduino-cli compile -b arduino:avr:uno /tmp/Arduino/alma/alma.ino
Error opening sketch: main file missing from sketch: /tmp/Arduino/alma/alma.ino

$ arduino-cli compile -b arduino:avr:uno /tmp/Arduino/alma/nonexistent
Error opening sketch: main file missing from sketch: /tmp/Arduino/alma/nonexistent/nonexistent.ino

Does this PR introduce a breaking change, and is
titled accordingly?
No

[kittaakos]

main file missing from sketch: /tmp/Arduino/alma/alma.ino

I am not sure about it. The problem is not the missing main file from the sketch, but the sketch does not exist.

[cmaglie]

Ok, it should be better now:

$ mkdir /tmp/Arduino
$ arduino-cli compile -b arduino:avr:uno /tmp/Arduino/alma
Error opening sketch: no such file or directory: /tmp/Arduino/alma

$ arduino-cli compile -b arduino:avr:uno /tmp/Arduino/alma/alma.ino
Error opening sketch: no such file or directory: /tmp/Arduino/alma/alma.ino

$ arduino-cli compile -b arduino:avr:uno /tmp/Arduino/alma/nonexistent
Error opening sketch: no such file or directory: /tmp/Arduino/alma/nonexistent

$ mkdir /tmp/Arduino/alma

$ arduino-cli compile -b arduino:avr:uno /tmp/Arduino/alma
Error opening sketch: main file missing from sketch: /tmp/Arduino/alma/alma.ino

$ arduino-cli compile -b arduino:avr:uno /tmp/Arduino/alma/alma.ino
Error opening sketch: no such file or directory: /tmp/Arduino/alma/alma.ino

$ arduino-cli compile -b arduino:avr:uno /tmp/Arduino/alma/nonexistent
Error opening sketch: no such file or directory: /tmp/Arduino/alma/nonexistent

$ touch /tmp/Arduino/alma/asd.ino

$ arduino-cli compile -b arduino:avr:uno /tmp/Arduino/alma
Error opening sketch: main file missing from sketch: /tmp/Arduino/alma/alma.ino

$ arduino-cli compile -b arduino:avr:uno /tmp/Arduino/alma/asd.ino 
Error opening sketch: main file missing from sketch: /tmp/Arduino/alma/alma.ino

$ arduino-cli compile -b arduino:avr:uno /tmp/Arduino/alma/nonexistent
Error opening sketch: no such file or directory: /tmp/Arduino/alma/nonexistent