fix(ci): downgrade NDK r28 → r27 (r28 libdl.a has Invalid record bug)

Author: Itsusinn

.github/workflows/build.yml

@@ -136,7 +136,7 @@ jobs:
         uses: nttld/setup-ndk@v1
         id: setup-ndk
         with:
-          ndk-version: r28
+          ndk-version: r27
 
       - name: Download libcronet.a
         env: