build/status: remove old compatibility fields for metropolis/cloud

Change-Id: I5e314714b02e87b5f955798dd2bcf497de699ac9
Reviewed-on: https://review.monogon.dev/c/monogon/+/2405
Reviewed-by: Tim Windelschmidt <tim@monogon.tech>
Tested-by: Jenkins CI
diff --git a/metropolis/node/BUILD.bazel b/metropolis/node/BUILD.bazel
index f207107..ba5103c 100644
--- a/metropolis/node/BUILD.bazel
+++ b/metropolis/node/BUILD.bazel
@@ -198,5 +198,5 @@
     name = "os-release-info",
     os_id = "metropolis-node",
     os_name = "Metropolis Node",
-    stamp_var = "STABLE_METROPOLIS_version",
+    stamp_var = "STABLE_MONOGON_metropolis_version",
 )