etcd: delete bbolt presubmit jobs

We reverted these ARM64 jobs to the GitHub runners due to instability in
the Prow infrastructure (etcd-io/bbolt#917) and
the inability to enable XFS for the robustness tests
(#33737). These jobs
haven't been running for a long time
(#34468), so it's safe to
remove this file.

Author: ivanvc

config/jobs/etcd/etcd-bbolt-presubmits.yaml

@@ -11,7 +11,6 @@ dashboard_groups:
   - sig-etcd-etcd-manager
   - sig-etcd-website-presubmits
   - sig-etcd-raft-presubmits
-  - sig-etcd-bbolt-presubmits
   - sig-etcd-operator-presubmits
   - sig-etcd-operator-postsubmits
 
@@ -131,6 +130,5 @@ dashboards:
   - name: sig-etcd-etcd-manager
   - name: sig-etcd-website-presubmits
   - name: sig-etcd-raft-presubmits
-  - name: sig-etcd-bbolt-presubmits
   - name: sig-etcd-operator-presubmits
   - name: sig-etcd-operator-postsubmits