jobs/update-osmo-python: remove build3

build3 does not exist anymore, but it was still referenced here, leading
to the job waiting forever until build3 comes online.

Related: OS#6186
Change-Id: Idba77a3b9595c234ee21dfd1d0e267021a17bb03
diff --git a/jobs/update-osmo-python-on-slaves.yml b/jobs/update-osmo-python-on-slaves.yml
index 0842fba..fad1cf6 100644
--- a/jobs/update-osmo-python-on-slaves.yml
+++ b/jobs/update-osmo-python-on-slaves.yml
@@ -8,7 +8,6 @@
           values:
             - build2-deb10build-ansible
             - build2-deb11build-ansible
-            - build3-deb11build-ansible
             - build4-deb12build-ansible
             - host2-deb11build-ansible
             - rpi4-raspbian11build-ansible-1