fix(dependencies): update an unused duplicate dependency exception

This duplicate was removed by PR #3572, but other duplicates still exist.

deny.toml

@@ -46,9 +46,6 @@ skip-tree = [
     # ticket #2984: owo-colors dependencies
     { name = "color-eyre", version = "=0.5.11" },
 
-    # ticket #2998: hdrhistogram dependencies
-    { name = "hdrhistogram", version = "=6.3.4" },
-
     # ticket #3061: reqwest and minreq dependencies
     { name = "webpki-roots", version = "=0.18.0" },
 
@@ -59,6 +56,12 @@ skip-tree = [
     # alternative: downgrade Zebra to `bigint`
     { name = "bigint", version = "=4.4.3" },
 
+    # upgrade sentry, metrics-exporter-prometheus, reqwest, hyper,
+    # which needs #2953: upgrade tracing to the latest major version
+    #
+    # also wait for tower-test and tokio-test to upgrade
+    { name = "tokio-util", version = "=0.6.9" },
+
     # recent major version bumps
     # we should re-check these dependencies in February 2022