chore(deps): bump golang from 1.25.9-bookworm to 1.26.3-bookworm

Bumps golang from 1.25.9-bookworm to 1.26.3-bookworm.

---
updated-dependencies:
- dependency-name: golang
  dependency-version: 1.26.3-bookworm
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <support@github.com>

Author: dependabot[bot]

Dockerfile

@@ -5,7 +5,7 @@
 # Must override builder-base, not builder, since the latter is referred to later in the file and so must not be
 # directly replaced. See here, and note that "stage" parameter mentioned there has been renamed to
 # "build-context": https://github.com/docker/buildx/pull/904#issuecomment-1005871838
-FROM golang:1.25.9-bookworm@sha256:298734aec230b5f3e8cee450ce6d7eccc39f1797ba548ee90d57e9803030c6c3 AS builder-base
+FROM golang:1.26.3-bookworm@sha256:252599aeb51ad60b83e4d8821802068127c528c707cb7dd7afd93be057c6011c AS builder-base
 FROM --platform=$BUILDPLATFORM builder-base AS builder
 
 ARG TARGETARCH

Dockerfile.windows

@@ -5,7 +5,7 @@
 # Must override builder-base, not builder, since the latter is referred to later in the file and so must not be
 # directly replaced. See here, and note that "stage" parameter mentioned there has been renamed to
 # "build-context": https://github.com/docker/buildx/pull/904#issuecomment-1005871838
-FROM --platform=linux/$BUILDARCH golang:1.25.9-bookworm@sha256:298734aec230b5f3e8cee450ce6d7eccc39f1797ba548ee90d57e9803030c6c3 AS builder-base
+FROM --platform=linux/$BUILDARCH golang:1.26.3-bookworm@sha256:252599aeb51ad60b83e4d8821802068127c528c707cb7dd7afd93be057c6011c AS builder-base
 FROM --platform=linux/$BUILDARCH builder-base AS builder
 
 ARG TARGETARCH