update submodules and add ci cache

.gitlab-ci.yml

@@ -51,3 +51,6 @@ build-sots:
   script:
     - echo "Building Pokémon SotS"
     - make all
+
+  cache:
+    key: ${CI_COMMIT_REF_SLUG}

g3headers

@@ -1 +1 @@
-Subproject commit a2e68703dcfccb4ef2319f8fd79a8ea7803a63c7
+Subproject commit 732e4c1cc26397d8ac95c28886d29501b0baf5b4