Add free java tutorial to resources/websites section

[sjtushi]

I work at LabEx, a unique learning platform that has delivered thousands of free and paid hands-on labs over the past 7 years. This series of free Java tutorials is designed based on our Hands-on Labs. You can read them without logging in, and all exercises can be run on your local machine, making them perfect for beginners.

Please let me know if any changes are needed.

[JeNesSaisPas]

thank you

[akullpp]

Great, but doesn't really fit the list as it lists only major resources.