Update dockerfile dependencies (#4170)

This PR contains the following updates:

| Package | Type | Update | Change |
|---|---|---|---|
| [docker/dockerfile](https://redirect.github.com/moby/buildkit) |
syntax | digest | `4a43a54` → `2780b5c` |
| golang | stage | digest | `2389ebf` → `c2a1f7b` |

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stacks/flow.Dockerfile

@@ -1,6 +1,6 @@
 # syntax=docker/dockerfile:1.23@sha256:2780b5c3bab67f1f76c781860de469442999ed1a0d7992a5efdf2cffc0e3d769
 
-FROM golang:1.26-alpine@sha256:2389ebfa5b7f43eeafbd6be0c3700cc46690ef842ad962f6c5bd6be49ed82039 AS builder
+FROM golang:1.26-alpine@sha256:c2a1f7b2095d046ae14b286b18413a05bb82c9bca9b25fe7ff5efef0f0826166 AS builder
 RUN apk add --no-cache gcc geos-dev musl-dev
 WORKDIR /root/flow
 

stacks/peerdb-server.Dockerfile

@@ -1,4 +1,4 @@
-# syntax=docker/dockerfile:1@sha256:4a43a54dd1fedceb30ba47e76cfcf2b47304f4161c0caeac2db1c61804ea3c91
+# syntax=docker/dockerfile:1@sha256:2780b5c3bab67f1f76c781860de469442999ed1a0d7992a5efdf2cffc0e3d769
 
 FROM lukemathwalker/cargo-chef:latest-rust-1.93.0-alpine@sha256:fb285bf1dddc093cca6a6847f9ed6071d69ee1f22eb85c354d6e9697867907d2 AS chef