[#3571] fix(CI): Skip cron job in fork repo by default. (#3573)

### What changes were proposed in this pull request?

Skip running cron-integration-test job in fork repo by default.

### Why are the changes needed?

Fix: #3571 

### Does this PR introduce _any_ user-facing change?

N/A

### How was this patch tested?

Test on fork repo:

<img width="1504" alt="image"
src="https://github.com/datastrato/gravitino/assets/154112360/da9500ef-e4d8-4528-9730-922fbd4f3f95">

.github/workflows/cron-integration-test.yml

@@ -11,6 +11,7 @@ concurrency:
 
 jobs:
   changes:
+    if: github.repository == 'datastrato/gravitino'
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v3
@@ -97,4 +98,4 @@ jobs:
             integration-test/build/integration-test.log
             distribution/package/logs/gravitino-server.out
             distribution/package/logs/gravitino-server.log
-            catalogs/**/*.log
+            catalogs/**/*.log