Use rand 0.8 again (#1567)

MinerSebas · MinerSebas · commit b2d654cbf6a4 · 2021-03-06T00:53:42.000Z
#1525 accidentally moved back to rand 0.7
diff --git a/crates/bevy_ecs/Cargo.toml b/crates/bevy_ecs/Cargo.toml
@@ -30,5 +30,5 @@ fxhash = "0.2"
 thiserror = "1.0"
 downcast-rs = "1.2"
 parking_lot = "0.11"
-rand = "0.7"
+rand = "0.8"
 serde = "1"
