Fix library header for cpp3 library.

Author: sebadoom

views/website/libraries/cpp3.pug

@@ -1,5 +1,5 @@
 // C++ arun11299/cpp-jwt
-article.cpp-jwt.cpp.accordion(data-accordion)
+article.jwt-cpp.cpp.accordion(data-accordion)
   .panel-heading(data-control)
     img(src='/img/26.svg')
     h3 C++