PluginInfo: Make output of failing PluginsRepositoryTest more readable

If you have additional plugins in your working tree the
corePluginsRepositoryShouldReturnCorePluginsFromReleaseWar test fails
(as expected) but it's output is rather unreadable [1]. Make it nicer
[2].

[1]
1) corePluginsRepositoryShouldReturnCorePluginsFromReleaseWar(com.googlesource.gerrit.plugins.manager.repository.PluginsRepositoryTest)
value of    : iterable.size()
expected    : 11
but was     : 12
iterable was: [com.googlesource.gerrit.plugins.manager.repository.PluginInfo@3da6950f, com.googlesource.gerrit.plugins.manager.repository.PluginInfo@42684d86, com.googlesource.gerrit.plugins.manager.repository.PluginInfo@45a05350, com.googlesource.gerrit.plugins.manager.repository.PluginInfo@7d6a9d5e, com.googlesource.gerrit.plugins.manager.repository.PluginInfo@74ed7111, com.googlesource.gerrit.plugins.manager.repository.PluginInfo@74691677, com.googlesource.gerrit.plugins.manager.repository.PluginInfo@3314f179, com.googlesource.gerrit.plugins.manager.repository.PluginInfo@1abd1a28, com.googlesource.gerrit.plugins.manager.repository.PluginInfo@5478597, com.googlesource.gerrit.plugins.manager.repository.PluginInfo@39a1e1e6, com.googlesource.gerrit.plugins.manager.repository.PluginInfo@2daa5092, com.googlesource.gerrit.plugins.manager.repository.PluginInfo@5f346355]
	at com.googlesource.gerrit.plugins.manager.repository.PluginsRepositoryTest.corePluginsRepositoryShouldReturnCorePluginsFromReleaseWar(PluginsRepositoryTest.java:60)

[2]
1) corePluginsRepositoryShouldReturnCorePluginsFromReleaseWar(com.googlesource.gerrit.plugins.manager.repository.PluginsRepositoryTest)
unexpected (1): checks

Change-Id: I520c4b918ad1b1a7bccea7e48afe1ea271aff5b5
---
expected      : [codemirror-editor, commit-message-length-validator, delete-project, download-commands, gitiles, hooks, plugin-manager, replication, reviewnotes, singleusergroup, webhooks]
but was       : [checks, codemirror-editor, commit-message-length-validator, delete-project, download-commands, gitiles, hooks, plugin-manager, replication, reviewnotes, singleusergroup, webhooks]
	at com.googlesource.gerrit.plugins.manager.repository.PluginsRepositoryTest.corePluginsRepositoryShouldReturnCorePluginsFromReleaseWar(PluginsRepositoryTest.java:61)

Change-Id: Iaac0ea0a421ba97b443ed99ba152323b77d79515
Signed-off-by: Edwin Kempin <ekempin@google.com>
diff --git a/src/test/java/com/googlesource/gerrit/plugins/manager/repository/PluginsRepositoryTest.java b/src/test/java/com/googlesource/gerrit/plugins/manager/repository/PluginsRepositoryTest.java
index 7989d4e..31f39f8 100644
--- a/src/test/java/com/googlesource/gerrit/plugins/manager/repository/PluginsRepositoryTest.java
+++ b/src/test/java/com/googlesource/gerrit/plugins/manager/repository/PluginsRepositoryTest.java
@@ -57,8 +57,6 @@
     Files.createSymbolicLink(site.gerrit_war, pathToReleaseWar);
 
     Collection<PluginInfo> plugins = pluginRepo.list(Version.getVersion());
-    assertThat(plugins).hasSize(GERRIT_CORE_PLUGINS.size());
-
     assertThat(plugins.stream().map(p -> p.name).sorted().collect(toList()))
         .containsExactlyElementsIn(GERRIT_CORE_PLUGINS)
         .inOrder();