fix a couple more memory leaks

src/Window.zig

@@ -632,6 +632,7 @@ pub fn destroy(self: *Window) void {
 
     self.font_group.deinit(self.alloc);
     self.font_lib.deinit();
+    self.alloc.destroy(self.font_group);
 
     self.alloc_io_arena.deinit();
     self.alloc.destroy(self.renderer_state.mutex);

src/input/Binding.zig

@@ -171,6 +171,11 @@ pub const Set = struct {
     /// The set of bindings.
     bindings: HashMap = .{},
 
+    pub fn deinit(self: *Set, alloc: Allocator) void {
+        self.bindings.deinit(alloc);
+        self.* = undefined;
+    }
+
     /// Add a binding to the set. If the binding already exists then
     /// this will overwrite it.
     pub fn put(self: *Set, alloc: Allocator, t: Trigger, action: Action) !void {