fix: declare execa as dependency in cli-tools (#2292)

Author: jbroma

packages/cli-tools/package.json

@@ -9,6 +9,7 @@
   "dependencies": {
     "appdirsjs": "^1.2.4",
     "chalk": "^4.1.2",
+    "execa": "^5.0.0",
     "find-up": "^5.0.0",
     "mime": "^2.4.1",
     "node-fetch": "^2.6.0",