Add Sensirion arduino-i2c-stcc4 to repositories.txt

[qfisch]

No description provided.

[github-actions]

Arduino Lint has suggestions for possible improvements to https://github.com/Sensirion/arduino-i2c-stcc4:

Linting library in arduino-i2c-stcc4
INFO: No header file found matching library name (Sensirion_I2C_STCC4.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 name Sensirion I2C STCC4 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)                                                                                                   

Linter results for project: 0 ERRORS, 1 WARNINGS

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Linting sketch in arduino-i2c-stcc4/examples/exampleUsage

Linter results for project: no errors or warnings

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Linting sketch in arduino-i2c-stcc4/examples/exampleUsageSingleShot

Linter results for project: no errors or warnings

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Linter results for projects: 0 ERRORS, 1 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/Sensirion/arduino-i2c-stcc4/