fix health reset on feeding

battlesnake/src/types/simulation.rs

@@ -458,12 +458,12 @@ impl Snake {
     pub fn advance(&mut self, head: Coord) {
         self.body.push_back(head);
         self.body.pop_front();
-        self.health = 100;
     }
 
     pub fn feed(&mut self) {
         if let Some(tail) = self.body.front() {
             self.body.push_front(*tail);
+            self.health = 100;
         }
     }
 }