Update 'next' version and dependencies in pnpm-lock.yaml

This commit updates the package version of 'next' from 14.3.0-canary.7 to 14.3.0-canary.9 throughout the pnpm-lock.yaml file. Other dependencies updated with the respective package include '@makerkit/data-loader-supabase-nextjs', '@keystatic/next' and so on. This update is important to ensure the latest features are being utilized while retaining compatibility with existing code.

packages/cms/core/src/create-cms-client.ts

@@ -50,7 +50,10 @@ async function getKeystaticClient() {
 function mockCMSClient() {
   return {
     getContentItems() {
-      return Promise.resolve([]);
+      return Promise.resolve({
+        items: [],
+        total: 0,
+      });
     },
     getContentItemBySlug() {
       return Promise.resolve(undefined);