chore(deps): update alpine:3 docker digest to c5b1261 (#7)

This PR contains the following updates:

| Package | Type | Update | Change |
|---|---|---|---|
| alpine | final | digest | `51b6726` -> `c5b1261` |
| alpine | stage | digest | `51b6726` -> `c5b1261` |

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Reviewed-on: #7
Co-authored-by: Renovate Bot <renovate@mgrote.net>
Co-committed-by: Renovate Bot <renovate@mgrote.net>

Dockerfile

@@ -1,4 +1,4 @@
-FROM alpine:3@sha256:51b67269f354137895d43f3b3d810bfacd3945438e94dc5ac55fdac340352f48 AS builder
+FROM alpine:3@sha256:c5b1261d6d3e43071626931fc004f70149baeba2c8ec672bd4f27761f8e1ad6b AS builder
 ARG MDNS_REPEATER_VERSION=local
 WORKDIR /
 COPY mdns-repeater.c mdns-repeater.c
@@ -7,7 +7,7 @@ RUN set -ex && \
     apk add --no-cache build-base && \
     gcc -o /bin/mdns-repeater mdns-repeater.c -DMDNS_REPEATER_VERSION=\"${MDNS_REPEATER_VERSION}\"
 
-FROM alpine:3@sha256:51b67269f354137895d43f3b3d810bfacd3945438e94dc5ac55fdac340352f48
+FROM alpine:3@sha256:c5b1261d6d3e43071626931fc004f70149baeba2c8ec672bd4f27761f8e1ad6b
 # hadolint ignore=DL3018
 RUN set -ex && \
     apk add --no-cache vlan libcap bash