Turn unlock/unlocknotify into plain arrays

They're always fixed-size, so there's no need to them to be a dynamic
vector.

I changed their type to `bool` too because they don't need to be `int`s.

Also, I replaced the hardcoded 25 constant with at least a name, in case
people want to change it in the future.

desktop_version/src/Game.h

@@ -288,8 +288,9 @@ public:
 
     std::vector<bool> quick_crewstats;
 
-    std::vector<int> unlock;
-    std::vector<int> unlocknotify;
+    static const int numunlock = 25;
+    bool unlock[numunlock];
+    bool unlocknotify[numunlock];
     bool anything_unlocked();
     int stat_trinkets;
     bool fullscreen;