cloud/bmaas/bmdb: implement BMDB client metrics

This implements some basic BMDB metrics exported by any client code
using the BMDB.

It also enables their use in the Shepherd and BMSRV.

Change-Id: I1d5e82fd2c34a7bfd42f37fad540d69f7b23f347
Reviewed-on: https://review.monogon.dev/c/monogon/+/1600
Tested-by: Jenkins CI
Reviewed-by: Tim Windelschmidt <tim@monogon.tech>
diff --git a/cloud/bmaas/bmdb/BUILD.bazel b/cloud/bmaas/bmdb/BUILD.bazel
index 761baef..c4eb226 100644
--- a/cloud/bmaas/bmdb/BUILD.bazel
+++ b/cloud/bmaas/bmdb/BUILD.bazel
@@ -10,12 +10,14 @@
     importpath = "source.monogon.dev/cloud/bmaas/bmdb",
     visibility = ["//visibility:public"],
     deps = [
+        "//cloud/bmaas/bmdb/metrics",
         "//cloud/bmaas/bmdb/model",
         "//cloud/bmaas/bmdb/reflection",
         "//cloud/lib/component",
         "@com_github_cockroachdb_cockroach_go_v2//crdb",
         "@com_github_google_uuid//:uuid",
         "@com_github_lib_pq//:pq",
+        "@com_github_prometheus_client_golang//prometheus",
         "@io_k8s_klog_v2//:klog",
     ],
 )