Bump alpine from 3.21.2 to 3.21.3 in /examples/hotrod (jaegertracing#…

…6740)

Bumps alpine from 3.21.2 to 3.21.3.


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examples/hotrod/Dockerfile

@@ -1,7 +1,7 @@
 # Copyright (c) 2024 The Jaeger Authors.
 # SPDX-License-Identifier: Apache-2.0
 
-FROM alpine:3.21.2 AS cert
+FROM alpine:3.21.3 AS cert
 RUN apk add --update --no-cache ca-certificates
 
 FROM scratch