Merge pull request #2768 from arduino/mcmchris/plc-ide/docs-link-fix

[PXCT-1492] Update PLC IDE tutorial to use Arduino Library Reference

Author: mcmchris

content/software/plc-ide/tutorials/02.plc-programming-introduction/content.md

@@ -138,9 +138,9 @@ With the 'Sketch Libraries' window open, click the **Add** option and fill out t
 
 For example, if you want to add the 1.1.1 version of the 'Arduino_MachineControl' library, respective information must be introduced to its fields accordingly.
 
-It is possible to find this information using the [Arduino Library List](https://www.arduinolibraries.info/) or referencing the indexed library on your development environment if you have downloaded it to use within Arduino IDE. By navigating manually to the local libraries directory on your development environment, you can access the meta-data from the 'library.properties' of the desired library.
+It is possible to find this information using the [Arduino Library Reference](https://docs.arduino.cc/libraries/) or referencing the indexed library on your development environment if you have downloaded it to use within Arduino IDE. By navigating manually to the local libraries directory on your development environment, you can access the meta-data from the 'library.properties' of the desired library.
 
-***Currently only publicly available libraries can be added to the PLC IDE Arduino Sketch, and you can check its availability by searching in the [Arduino Library List](https://www.arduinolibraries.info/).***
+***Currently only publicly available libraries can be added to the PLC IDE Arduino Sketch, and you can check its availability by searching in the [Arduino Library Reference](https://docs.arduino.cc/libraries/).***
 
 Once you have followed the previous steps, the libraries will be available for use. A library of choice can be removed by clicking on the **Remove** option within the 'Sketch Libraries' window.