workflow: update size report to compare against pr target branch

Author: yyx990803

.github/workflows/size-data.yml

@@ -4,6 +4,7 @@ on:
   push:
     branches:
       - main
+      - minor
   pull_request:
     branches:
       - main

.github/workflows/size-report.yml

@@ -58,7 +58,7 @@ jobs:
       - name: Download Previous Size Data
         uses: dawidd6/action-download-artifact@v6
         with:
-          branch: main
+          branch: ${{ github.base_ref }}
           workflow: size-data.yml
           event: push
           name: size-data