Get plugin-manager and uploadvalidator from 2.15 branch

Plugin-manager and uploadvalidator have now stable branches for
compatibility with Gerrit v2.15.

Change-Id: If38657660f1101a8ee05c6d7a21df47e58e46b02
diff --git a/fpm/Makefile b/fpm/Makefile
index 82c72e7..03ab15f 100644
--- a/fpm/Makefile
+++ b/fpm/Makefile
@@ -23,11 +23,11 @@
 LIBS_JOBS= \
   plugin-out-of-the-box-bazel-master-stable-2.15/lastSuccessfulBuild/artifact/bazel-genfiles/plugins/out-of-the-box/out-of-the-box.jar
 PLUGINS_JOBS= \
-  plugin-plugin-manager-bazel-master-stable-2.15/lastSuccessfulBuild/artifact/bazel-genfiles/plugins/plugin-manager/plugin-manager.jar \
+  plugin-plugin-manager-bazel-stable-2.15/lastSuccessfulBuild/artifact/bazel-genfiles/plugins/plugin-manager/plugin-manager.jar \
   plugin-avatars-gravatar-bazel-master-stable-2.15/lastSuccessfulBuild/artifact/bazel-genfiles/plugins/avatars-gravatar/avatars-gravatar.jar \
   plugin-gitiles-bazel-stable-2.15/lastSuccessfulBuild/artifact/bazel-genfiles/plugins/gitiles/gitiles.jar \
   plugin-delete-project-bazel-stable-2.15/lastSuccessfulBuild/artifact/bazel-genfiles/plugins/delete-project/delete-project.jar \
-  plugin-uploadvalidator-bazel-master-stable-2.15/lastSuccessfulBuild/artifact/bazel-genfiles/plugins/uploadvalidator/uploadvalidator.jar
+  plugin-uploadvalidator-bazel-stable-2.15/lastSuccessfulBuild/artifact/bazel-genfiles/plugins/uploadvalidator/uploadvalidator.jar
 
 RPM_OUT=$(OUT)/gerrit-$(VERSION)-$(RELEASE).$(BUILD_ARCH).rpm
 DEB_OUT=$(OUT)/gerrit-$(VERSION)-$(RELEASE).$(BUILD_ARCH).deb