Update dependencies

app/src/other/java/io/nekohasekai/sfa/vendor/Vendor.kt

@@ -11,6 +11,9 @@ object Vendor : VendorInterface {
     override fun checkUpdate(activity: Activity, byUser: Boolean) {
     }
 
+    override fun initializeBillingClient(activity: Activity) {
+    }
+
     override fun startSponsor(activity: Activity, fallback: () -> Unit) {
         fallback()
     }