Make net cts not using isolated storage

Disabling isolated storage so existing tests can still write files to
/sdcard and shell can read it successfully.

Bug: 124651276
Test: atest android.net.cts.NetworkWatchlistTest#testGetWatchlistConfigHash
Change-Id: I6c40d1ae12fc2cff76c976c11650423df5ce044f
diff --git a/tests/cts/net/AndroidTest.xml b/tests/cts/net/AndroidTest.xml
index 76ff167..ff93afc 100644
--- a/tests/cts/net/AndroidTest.xml
+++ b/tests/cts/net/AndroidTest.xml
@@ -26,5 +26,6 @@
         <option name="package" value="android.net.cts" />
         <option name="runtime-hint" value="9m4s" />
         <option name="hidden-api-checks" value="false" />
+        <option name="isolated-storage" value="false" />
     </test>
 </configuration>