Vagrantfile: add dependencies for building the docs
Vagrantfile: add dependencies for building the docs

Required by the test to check external links. Being able to build the
docs by default in the VM is also nice.

Signed-off-by: Alexander Alemayhu <e46fc836cca3acec03944314d1457c2ae6c68ef3@alemayhu.com>

cilium/cilium,tgraf/cilium,scanf/cilium,cilium/cilium,tklauser/cilium,mskarbek/cilium,eloycoto/cilium,eloycoto/cilium,cilium/cilium,cilium-team/cilium,gumpt/cilium,eloycoto/cilium,scanf/cilium,eloycoto/cilium,tgraf/cilium,cilium/cilium,michi-covalent/cilium,gumpt/cilium,cilium-team/cilium,michi-covalent/cilium,gumpt/cilium,tklauser/cilium,eloycoto/cilium,gumpt/cilium,tklauser/cilium,tgraf/cilium,mskarbek/cilium,scanf/cilium,michi-covalent/cilium,gumpt/cilium,mskarbek/cilium,scanf/cilium,tgraf/cilium,scanf/cilium,scanf/cilium,eloycoto/cilium,gumpt/cilium,eloycoto/cilium,tklauser/cilium,mskarbek/cilium,cilium/cilium,tgraf/cilium,tgraf/cilium,mskarbek/cilium,gumpt/cilium,mskarbek/cilium,scanf/cilium,tklauser/cilium,michi-covalent/cilium,michi-covalent/cilium