Add Henhen1227's BluetoothSerial Library

[per1234]

No description provided.

[github-actions]

Arduino Lint has suggestions for possible improvements to https://github.com/hen1227/bluetooth-serial:

Linting library in bluetooth-serial
WARNING: Invalid category field value Bluetooth Communication in library.properties                            
         See: https://arduino.github.io/arduino-cli/latest/library-specification/#libraryproperties-file-format
         (Rule LP038)                                                                                          
WARNING: Unable to load the library.properties url field: 404 Not Found                                        
         See: https://arduino.github.io/arduino-cli/latest/library-specification/#libraryproperties-file-format
         (Rule LP042)                                                                                          
WARNING: No readme found. Please document your library.                                                                                
         See:                                                                                                                          
         https://docs.github.com/repositories/managing-your-repositorys-settings-and-features/customizing-your-repository/about-readmes
         (Rule LD001)                                                                                                                  
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: 0 ERRORS, 4 WARNINGS

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Linting sketch in bluetooth-serial/examples/Boiler_Plate

Linter results for project: no errors or warnings

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Linting sketch in bluetooth-serial/examples/Hello_World

Linter results for project: no errors or warnings

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

Linter results for projects: 0 ERRORS, 4 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/hen1227/bluetooth-serial/