Remove myself from clippy's highfive rotation.

I'm currently quite busy with my bachelor thesis, and new PR assignments are sadly a great way to procrastinate. Therefore, I'm removing myself from the Clippy rotation for a bit until I have more time again, which should be at the end of February.  I'll try to complete my current assignments, and I'm open for review requests as usual.

Author: xFrednet

highfive/configs/rust-lang/rust-clippy.json

@@ -1,6 +1,6 @@
 {
     "groups": {
-        "all": ["@flip1995", "@Manishearth", "@llogiq", "@camsteffen", "@giraffate", "@xFrednet"]
+        "all": ["@flip1995", "@Manishearth", "@llogiq", "@camsteffen", "@giraffate"]
     },
     "dirs": {
         ".github": ["@flip1995"]