chore(deps): update docker.io/library/alpine:3.21.0 docker digest to …

…21dc606

Signed-off-by: renovate[bot] <[email protected]>

Dockerfile

@@ -12,7 +12,7 @@ RUN make clean && make hubble
 # thread[1].
 # [0]: https://bugs.busybox.net/show_bug.cgi?id=12541
 # [1]: https://github.com/gliderlabs/docker-alpine/issues/539
-FROM docker.io/library/alpine:3.21.0@sha256:e323a465c03a31ad04374fc7239144d0fd4e2b92da6e3e0655580476d3a84621
+FROM docker.io/library/alpine:3.21.0@sha256:21dc6063fd678b478f57c0e13f47560d0ea4eeba26dfc947b2a4f81f686b9f45
 RUN apk add --no-cache bash curl jq
 COPY --from=builder /go/src/github.com/cilium/hubble/hubble /usr/bin
 CMD ["/usr/bin/hubble"]