doc(gsoc): Update the GSoC doc link
doc(gsoc): Update the GSoC doc link

Change-Id: I8fa200b6897c08f9f7a172d371a918775eccd993

shaka-project/shaka-player,tvoli/shaka-player,tvoli/shaka-player,tvoli/shaka-player,shaka-project/shaka-player,shaka-project/shaka-player,tvoli/shaka-player,shaka-project/shaka-player