Add Api type to manifest for BUCK build

Change-Id: I1055ab85ad7a536d16a4115641065ae5797ffb3f

BUCK

diff --git a/BUCK b/BUCK
index b05e695..ad2a7dd 100644
--- a/BUCK
+++ b/BUCK
@@ -5,6 +5,7 @@
   manifest_entries = [
     'Gerrit-Module: com.googlesource.gerrit.plugins.its.phabricator.PhabricatorModule',
     'Gerrit-ReloadMode: reload',
+    'Gerrit-ApiType: plugin',
     'Implementation-Title: Plugin its-phabricator',
     'Implementation-Vendor: Wikimedia Foundation',
     'Implementation-URL: https://gerrit.googlesource.com/plugins/its-phabricator',