Move to peerDependencies

scripts/build/build-package-json.js

@@ -100,10 +100,15 @@ async function buildPackageJson({ packageConfig, file }) {
       prepublishOnly:
         "node -e \"assert.equal(require('.').version, require('..').version)\"",
     },
-    dependencies: {
+    peerDependencies: {
       // Add `^` here, so we don't need release Prettier user can still update CLI
       "@prettier/cli": `^${packageJson.dependencies["@prettier/cli"]}`,
     },
+    peerDependenciesMeta: {
+      "@prettier/cli": {
+        optional: true,
+      },
+    },
   };
 
   await writeJson(