Update repositories.txt

[ddchung]

Add my non-blocking HC-SR04 Library

[github-actions]

Arduino Lint has suggestions for possible improvements to https://github.com/ddchung/Async-HC-SR04-Lib:

Linting library in Async-HC-SR04-Lib
INFO: No header file found matching library name (Distance-Sensor.h). Best practices are for primary header filename to 
      match library name.                                                                                               
      See: https://arduino.github.io/arduino-cli/latest/library-specification/#libraryproperties-file-format            
      (Rule LS008)                                                                                                      
WARNING: library.properties version value 1.0 is not compliant with the semver specification.
         See: https://semver.org/                                                            
         (Rule LP021)                                                                        
WARNING: Missing architectures field in library.properties                                                     
         See: https://arduino.github.io/arduino-cli/latest/library-specification/#libraryproperties-file-format
         (Rule LP043)                                                                                          

Linter results for project: 0 ERRORS, 2 WARNINGS

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Linting sketch in Async-HC-SR04-Lib/examples/hc-sr04

Linter results for project: no errors or warnings

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

Linter results for projects: 0 ERRORS, 2 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/ddchung/Async-HC-SR04-Lib/

[ddchung]

that was fast! great job on the bots!