🧹 Add common extensions to the devcontainer (LayerZero-Labs#388)

.devcontainer/devcontainer.json

@@ -11,5 +11,22 @@
     "ghcr.io/devcontainers/features/docker-in-docker:2": {
       "moby": false
     }
+  },
+  "customizations": {
+    "vscode": {
+      "extensions": [
+        "bdavs.expect",
+        "esbenp.prettier-vscode",
+        "formulahendry.docker-explorer",
+        "dbaeumer.vscode-eslint",
+        "jetmartin.bats",
+        "shd101wyy.markdown-preview-enhanced",
+        "redhat.vscode-yaml",
+        "JuanBlanco.solidity",
+        "ms-vscode.makefile-tools",
+        "me-dutour-mathieu.vscode-github-actions",
+        "tamasfe.even-better-toml"
+      ]
+    }
   }
 }