Add PY32LowPower library to repositories.txt

[regimantas]

Added https://github.com/regimantas/PY32LowPower for inclusion in the Arduino Library Manager.

[github-actions]

❌ ERROR: Arduino Lint found errors with https://github.com/regimantas/PY32LowPower:

Linting library in PY32LowPower
ERROR: Missing maintainer field in library.properties                                                        
       See: https://arduino.github.io/arduino-cli/latest/library-specification/#libraryproperties-file-format
       (Rule LP025)                                                                                          
WARNING: No license file found.                                                                                                                 
         See:                                                                                                                                   
         https://docs.github.com/repositories/managing-your-repositorys-settings-and-features/customizing-your-repository/licensing-a-repository
         (Rule LD002)                                                                                                                           

Linter results for project: 1 ERRORS, 1 WARNINGS

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

Linting sketch in PY32LowPower/examples/LowPowerSleep

Linter results for project: no errors or warnings

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

Linter results for projects: 1 ERRORS, 1 WARNINGS

[github-actions]

Thanks for your interest in contributing to the Arduino Library Manager index @regimantas
Please resolve the error(s) mentioned in the previous comment.

After resolving the issue, trigger this check again by doing one of the following:

• Commit the required change to the branch you submitted this pull request from.
• Comment here, mentioning @ArduinoBot in the comment.

❗ NOTE: It is not necessary to open a new pull request. ❗

More information:
https://github.com/arduino/library-registry/blob/main/README.md#if-the-problem-is-with-the-pull-request