Revert the mission center icon to the old version

[chrrybmb64]

• Distribution: Arch Linux
• Desktop environment: KDE
• Installing method: Pacman
• App name: Mission Center 0.5.2

Current Papirus icon / Old Papirus icon / Official icon ---------------- ------------

I was about to make an issue asking for some changes to the mission center icon, when I found that there is already an older version of it that looks exactly how I want it to. My issues with the current one are that firstly, it doesn't resemble the official icon due to it's change in color, and secondly, the black-on-black color is less visually pleasing than the old one's contrast of black and white. This makes it hard for people new to the icon pack to find mission center, and when they do, they may be displeased by it's seemingly random color change.