[vbmeta][test] Use testkeys from avb directly in tests

Bug: 256148034
Test: atest libvbmeta_rust.test
Change-Id: Ieeb611dbc747839e4e10badfbc55a022a8bf96de
diff --git a/libs/vbmeta/Android.bp b/libs/vbmeta/Android.bp
index c5078c2..a487097 100644
--- a/libs/vbmeta/Android.bp
+++ b/libs/vbmeta/Android.bp
@@ -27,7 +27,11 @@
         "libanyhow",
         "libtempfile",
     ],
-    data: ["tests/data/*"],
+    data: [
+        ":avb_testkey_rsa2048",
+        ":avb_testkey_rsa4096",
+        ":avb_testkey_rsa8192",
+    ],
     required: ["avbtool"],
     test_suites: ["general-tests"],
     test_options: {