Update github workflow to reduce resource occupy

Signed-off-by: yhmo <yihua.mo@zilliz.com>

Author: yhmo

.github/workflows/main.yaml

@@ -1,6 +1,10 @@
 name: Build and test
 on:
   push:
+    branches-ignore:
+      - master
+      - '2.*'
+      - '3.*'
     # file paths to consider in the event. Optional; defaults to all.
     paths:
       - 'cmake/**'