Dockerfile: use GOTOOLCHAIN=local

This may find its way into the official images, but until it does, let's
make sure we don't get unexpected updates of go.

Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
(cherry picked from commit e9759cee69)
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>

dockerfiles/Dockerfile.dev

@@ -7,7 +7,8 @@ ARG BUILDX_VERSION=0.11.2
 FROM docker/buildx-bin:${BUILDX_VERSION} AS buildx
 
 FROM golang:${GO_VERSION}-alpine${ALPINE_VERSION} AS golang
-ENV  CGO_ENABLED=0
+ENV GOTOOLCHAIN=local
+ENV CGO_ENABLED=0
 
 FROM golang AS gofumpt
 ARG GOFUMPT_VERSION=v0.4.0

dockerfiles/Dockerfile.lint

@@ -7,6 +7,7 @@ ARG GOLANGCI_LINT_VERSION=v1.54.2
 FROM golangci/golangci-lint:${GOLANGCI_LINT_VERSION}-alpine AS golangci-lint
 
 FROM golang:${GO_VERSION}-alpine${ALPINE_VERSION} AS lint
+ENV GOTOOLCHAIN=local
 ENV GO111MODULE=off
 ENV CGO_ENABLED=0
 ENV GOGC=75

dockerfiles/Dockerfile.vendor

@@ -5,6 +5,7 @@ ARG ALPINE_VERSION=3.17
 ARG MODOUTDATED_VERSION=v0.8.0
 
 FROM golang:${GO_VERSION}-alpine${ALPINE_VERSION} AS base
+ENV GOTOOLCHAIN=local
 RUN apk add --no-cache bash git rsync
 WORKDIR /src