chore(deps): update docker.io/library/alpine docker tag to v3.21.3

Signed-off-by: cilium-renovate[bot] <134692979+cilium-renovate[bot]@users.noreply.github.com>

Dockerfile

@@ -82,15 +82,15 @@ RUN curl -L https://github.com/libbpf/bpftool/releases/download/${BPFTOOL_TAG}/b
 
 # Get bash-completion manifests and generate tetra CLI bash
 # autocompletions (we don't want all bash-completions in the base-build)
-FROM docker.io/library/alpine:3.21.2@sha256:56fa17d2a7e7f168a043a2712e63aed1f8543aeafdcee47c58dcffe38ed51099 AS cli-autocomplete
+FROM docker.io/library/alpine:3.21.3@sha256:a8560b36e8b8210634f77d9f7f9efd7ffa463e380b75e2e74aff4511df3ef88c AS cli-autocomplete
 COPY --from=tetragon-builder /go/src/github.com/cilium/tetragon/tetra /usr/bin/
 RUN apk add --no-cache bash-completion && \
     tetra completion bash > /etc/bash_completion.d/tetra && \
     chmod a+r /etc/bash_completion.d/tetra
 
 # Almost final step runs on target platform (might need emulation) and
 # retrieves (cross-)compiled binaries from builders
-FROM docker.io/library/alpine:3.21.2@sha256:56fa17d2a7e7f168a043a2712e63aed1f8543aeafdcee47c58dcffe38ed51099 AS base-build
+FROM docker.io/library/alpine:3.21.3@sha256:a8560b36e8b8210634f77d9f7f9efd7ffa463e380b75e2e74aff4511df3ef88c AS base-build
 RUN apk add --no-cache iproute2
 RUN mkdir /var/lib/tetragon/ && \
     mkdir -p /etc/tetragon/tetragon.conf.d/ && \

Dockerfile.operator

@@ -3,7 +3,7 @@
 
 ARG BASE_IMAGE=scratch
 ARG GOLANG_IMAGE=docker.io/library/golang:1.23.5@sha256:51a6466e8dbf3e00e422eb0f7a97ac450b2d57b33617bbe8d2ee0bddcd9d0d37
-ARG ALPINE_IMAGE=docker.io/library/alpine:3.21.2@sha256:56fa17d2a7e7f168a043a2712e63aed1f8543aeafdcee47c58dcffe38ed51099
+ARG ALPINE_IMAGE=docker.io/library/alpine:3.21.3@sha256:a8560b36e8b8210634f77d9f7f9efd7ffa463e380b75e2e74aff4511df3ef88c
 
 # BUILDPLATFORM is an automatic platform ARG enabled by Docker BuildKit.
 # Represents the plataform where the build is happening, do not mix with

Dockerfile.rthooks

@@ -1,7 +1,7 @@
 # SPDX-License-Identifier: Apache-2.0
 
 ARG GOLANG_IMAGE=docker.io/library/golang:1.23.5@sha256:51a6466e8dbf3e00e422eb0f7a97ac450b2d57b33617bbe8d2ee0bddcd9d0d37
-ARG BASE_IMAGE=docker.io/library/alpine:3.21.2@sha256:56fa17d2a7e7f168a043a2712e63aed1f8543aeafdcee47c58dcffe38ed51099
+ARG BASE_IMAGE=docker.io/library/alpine:3.21.3@sha256:a8560b36e8b8210634f77d9f7f9efd7ffa463e380b75e2e74aff4511df3ef88c
 
 # BUILDPLATFORM is an automatic platform ARG enabled by Docker BuildKit.
 # Represents the plataform where the build is happening, do not mix with