Escape {} for owners plugin script

JJB interprets the {} as parameter substitution, we need to make
sure to escape them on the owners plugin to use them for Bash
expressions.

Change-Id: Iaaca03501d2d0862923b43a85372ecdd80b4a809
diff --git a/jenkins/gerrit-bazel-build-owners-plugin-branch.sh b/jenkins/gerrit-bazel-build-owners-plugin-branch.sh
index 291b834..991a318 100644
--- a/jenkins/gerrit-bazel-build-owners-plugin-branch.sh
+++ b/jenkins/gerrit-bazel-build-owners-plugin-branch.sh
@@ -3,7 +3,7 @@
 git checkout -f gerrit/{gerrit-branch}
 git read-tree -u --prefix=plugins/{name}-plugin origin/{branch}
 ln -s owners-plugin/owners-common .
-pushd plugins && ln -s owners-plugin/{owners,owners-autoassign} . && popd
+pushd plugins && ln -s owners-plugin/{{owners,owners-autoassign}} . && popd
 
 if [ -f plugins/{name}-plugin/external_plugin_deps.bzl ]
 then
diff --git a/jenkins/gerrit-bazel-build-owners-plugin.sh b/jenkins/gerrit-bazel-build-owners-plugin.sh
index 4d42b65..e387b41 100644
--- a/jenkins/gerrit-bazel-build-owners-plugin.sh
+++ b/jenkins/gerrit-bazel-build-owners-plugin.sh
@@ -3,7 +3,7 @@
 git checkout -f gerrit/{branch}
 git read-tree -u --prefix=plugins/{name}-plugin origin/{branch}
 ln -s owners-plugin/owners-common .
-pushd plugins && ln -s owners-plugin/{owners,owners-autoassign} . && popd
+pushd plugins && ln -s owners-plugin/{{owners,owners-autoassign}} . && popd
 
 if [ -f plugins/{name}-plugin/external_plugin_deps.bzl ]
 then