Add upgrade note for #9553. (#9563)

* Add upgrade note for #9553.
* Note that these are metrics introduced in 1.5.0.
* Added link to docs.

website/pages/docs/upgrading/upgrade-to-1.5.0.mdx

@@ -10,7 +10,7 @@ description: |-
 # Overview
 
 This page contains the list of deprecations and important or breaking changes
-for Vault 1.4.x compared to 1.5.0. Please read it carefully.
+for Vault 1.5.0 compared to 1.4.1. Please read it carefully.
 
 ## Raft Configuration
 
@@ -24,3 +24,18 @@ In addition, a new metric has been introduced, `vault.raft-storage.entry_size`,
 that allows for operators to sample the entry size, view the average, and adjust
 the configuration value as necessary. For additional details, please see
 [Raft configuration](docs/configuration/storage/raft).
+
+## Known Issues
+
+Enabling telemetry on 32-bit systems will cause Vault to crash.  A workaround for this
+issue is to disable collection of usage gauges in the [telemetry](docs/configuration/telemetry) stanza of the configuration.
+
+```
+telemetry {
+  ...
+  usage_gauge_period = "none"
+}
+```
+
+This will suppress the metrics `vault.identity.entity.count`, `vault.identity.entity.alias.count`, `vault.token.count`, `vault.token.count.by_auth`, `vault.token.count.by_policy`, `vault.token.count.by_ttl` and `vault.secret.kv.count` that were introduced in version 1.5.0, but all other Vault telemetry will remain available.
+