Update repositories.txt

[mkeras]

No description provided.

[github-actions]

Arduino Lint has suggestions for possible improvements to https://github.com/mkeras/EmbeddedSparkplugNode:

Linting library in EmbeddedSparkplugNode
INFO: No header file found matching library name (EmbeddedSparkplugNode.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 value EmbeddedSparkplugNode 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 depends field item(s) BasicTag (>=1.3.2) not found in the Library Manager index.   
         See: https://arduino.github.io/arduino-cli/latest/library-specification/#libraryproperties-file-format
         (Rule LP048)                                                                                          
WARNING: library.properties includes field item(s) BasicTag.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

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

Linting sketch in EmbeddedSparkplugNode/examples/example_sparkplug_node

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/mkeras/EmbeddedSparkplugNode/