Make some temporary sounds for each of the build actions.

.tarpit.json

@@ -1,9 +1,9 @@
 {
   "audio": {
-    "you_died": "./assets/you_died.wav",
-    "build_works": "./assets/build_works.wav",
-    "build_failed": "./assets/build_failed.wav",
-    "building": "./assets/building.wav"
+    "you_died": "./assets/you_died.mp3",
+    "build_works": "./assets/build_works.mp3",
+    "build_failed": "./assets/build_failed.mp3",
+    "building": "./assets/nothing.mp3"
   },
   "git_path": ".\\",
   "build_cmd": "meson compile -C builddir"