Add `UseLocalDisk` annotation to fix test

Something changed in the gerrit-plugin-api package between versions 3.7
and 3.8, so `openRepository` was returning an `InMemoryRepository`
instead of a `FileRepository`.

Adding this annotation makes the method return a `FileRepository` and
fixes this test.

Oddly this happened in CI and we couldn't recreate it locally.

Change-Id: Idf1ef771b07df5febead21cd69bc00d8942b1536

src/test/scala/com/googlesource/gerrit/plugins/analytics/test/GerritTestDaemon.scala

diff --git a/src/test/scala/com/googlesource/gerrit/plugins/analytics/test/GerritTestDaemon.scala b/src/test/scala/com/googlesource/gerrit/plugins/analytics/test/GerritTestDaemon.scala
index 2feb82d..dd79434 100644
--- a/src/test/scala/com/googlesource/gerrit/plugins/analytics/test/GerritTestDaemon.scala
+++ b/src/test/scala/com/googlesource/gerrit/plugins/analytics/test/GerritTestDaemon.scala
@@ -140,6 +140,7 @@
   }
 }
 
+@UseLocalDisk
 @TestPlugin(
   name = "analytics",
   sysModule = "com.googlesource.gerrit.plugins.analytics.test.GerritTestDaemon$TestModule"