chore(CHANGELOG.md): apply correct whitespace padding for bullets
chore(CHANGELOG.md): apply correct whitespace padding for bullets

The second level bullet points required an additional space for
them to generate as second level bullets in markdown.

virror/VRTK,Fulby/VRTK,red-horizon/VRTK,adamjweaver/VRTK,mattboy64/SteamVR_Unity_Toolkit,gpvigano/SteamVR_Unity_Toolkit,thestonefox/SteamVR_Unity_Toolkit,gomez-addams/SteamVR_Unity_Toolkit,gpvigano/VRTK,TMaloteaux/SteamVR_Unity_Toolkit,thestonefox/VRTK,Innoactive/IA-unity-VR-toolkit-VRTK