Update repositories.txt

[atulravi]

Added AtrivaTECH_PicUNO library to repositories list.

[github-actions]

Arduino Lint has suggestions for possible improvements to https://github.com/AtrivaTECH/AtrivaTECH_PicUNO:

Linting library in AtrivaTECH_PicUNO
WARNING: library.properties name value AtrivaTECH PicUNO is longer than the recommended length of 16 characters.
         See: https://arduino.github.io/arduino-cli/latest/library-specification/#libraryproperties-file-format 
         (Rule LP010)                                                                                           
WARNING: library.properties name AtrivaTECH PicUNO contains spaces. Although supported, best practices is to not use    
         spaces.                                                                                                        
         See: https://arduino.github.io/arduino-cli/latest/library-specification/#libraryproperties-file-format         
         (Rule LP015)                                                                                                   
WARNING: library.properties includes field item(s) Arduino.h not found in library.                             
         See: https://arduino.github.io/arduino-cli/latest/library-specification/#libraryproperties-file-format
         (Rule LP052)                                                                                          

Linter results for project: 0 ERRORS, 3 WARNINGS

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Linting sketch in AtrivaTECH_PicUNO/examples/All_Features

Linter results for project: no errors or warnings

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Linting sketch in AtrivaTECH_PicUNO/examples/Analog/Potentiometer

Linter results for project: no errors or warnings

-------------------

Linting sketch in AtrivaTECH_PicUNO/examples/Blink

Linter results for project: no errors or warnings

-------------------

Linting sketch in AtrivaTECH_PicUNO/examples/Fade

Linter results for project: no errors or warnings

-------------------

Linter results for projects: 0 ERRORS, 3 WARNINGS

[github-actions]

Your submission has now been accepted! Thanks for your contribution to the Arduino Library Manager index.

The library(s) will be available for installation via Library Manager within a day's time.

You can check the logs from the Library Manager indexer for your library(s) here:
http://downloads.arduino.cc/libraries/logs/github.com/AtrivaTECH/AtrivaTECH_PicUNO/