fix(GETTING_STARTED.md): update oculus utilities download link
fix(GETTING_STARTED.md): update oculus utilities download link

The download link for Oculus Utilities was set to an old version of
1.10 which is no longer supported. The link has been updated to
point to whatever the latest version of Oculus Utilities is available.
gpvigano/SteamVR_Unity_Toolkit,Fulby/VRTK,Innoactive/IA-unity-VR-toolkit-VRTK,virror/VRTK,thestonefox/VRTK,gomez-addams/SteamVR_Unity_Toolkit,thestonefox/SteamVR_Unity_Toolkit,red-horizon/VRTK,gpvigano/VRTK,TMaloteaux/SteamVR_Unity_Toolkit,adamjweaver/VRTK,mattboy64/SteamVR_Unity_Toolkit