Additional Reference (#20281)
Additional Reference (#20281)

Added WebPlatform external html lists reference list.
HKuz/FreeCodeCamp,raisedadead/FreeCodeCamp,BhaveshSGupta/FreeCodeCamp,jonathanihm/freeCodeCamp,FreeCodeCamp/FreeCodeCamp,HKuz/FreeCodeCamp,FreeCodeCamp/FreeCodeCamp,jonathanihm/freeCodeCamp,BhaveshSGupta/FreeCodeCamp,BhaveshSGupta/FreeCodeCamp,raisedadead/FreeCodeCamp