Update repositories.txt (#4643)

Adding R4_Touch library

Author: delta-G

repositories.txt

@@ -1656,6 +1656,7 @@ https://github.com/delta-G/EventLinkInterrupt
 https://github.com/delta-G/GPT_Stepper
 https://github.com/delta-G/LoveButton
 https://github.com/delta-G/PID_DG
+https://github.com/delta-G/R4_Touch
 https://github.com/deltarobotone/one_system_library
 https://github.com/deneyapkart/deneyap_arduino_examples
 https://github.com/deneyapkart/deneyap-5x7-led-matris-arduino-library