make getDefaultProvider static

Test: atest aconfig_storage_package aconfig_storage_file.test.java
Bug: 367765164
Flag: EXEMPT refactor
Change-Id: I92d407d03e91c4fa223abdc06a64cbae36ff5074
diff --git a/tools/aconfig/aconfig_storage_read_api/srcs/android/aconfig/storage/StorageFileProvider.java b/tools/aconfig/aconfig_storage_read_api/srcs/android/aconfig/storage/StorageFileProvider.java
index 6a6f007..f586150 100644
--- a/tools/aconfig/aconfig_storage_read_api/srcs/android/aconfig/storage/StorageFileProvider.java
+++ b/tools/aconfig/aconfig_storage_read_api/srcs/android/aconfig/storage/StorageFileProvider.java
@@ -40,7 +40,7 @@
     private final String mBootPath;
 
     /** @hide */
-    public StorageFileProvider getDefaultProvider() {
+    public static StorageFileProvider getDefaultProvider() {
         return new StorageFileProvider(DEFAULT_MAP_PATH, DEFAULT_BOOT_PATH);
     }