Adapt to bazel 9.1.0 update

Change-Id: Id638bf08bdc82be147e8ba9c26d504f21a03aa12

src/main/java/com/googlesource/gerrit/plugins/reviewersbyblame/ChangeUpdatedListener.java

diff --git a/src/main/java/com/googlesource/gerrit/plugins/reviewersbyblame/ChangeUpdatedListener.java b/src/main/java/com/googlesource/gerrit/plugins/reviewersbyblame/ChangeUpdatedListener.java
index c421479..209cf06 100644
--- a/src/main/java/com/googlesource/gerrit/plugins/reviewersbyblame/ChangeUpdatedListener.java
+++ b/src/main/java/com/googlesource/gerrit/plugins/reviewersbyblame/ChangeUpdatedListener.java
@@ -143,7 +143,7 @@
                   try {
                     task.run();
                   } finally {
-                    tl.setContext(old);
+                    var unused = tl.setContext(old);
                   }
                 }
               });