adjust docker build and co.

Dockerfile

@@ -1,9 +1,9 @@
-FROM golang:1.19 AS builder
+FROM golang:1.23 AS builder
 WORKDIR /go/src/github.com/prometheus-community/jiralert
 COPY . /go/src/github.com/prometheus-community/jiralert
 RUN GO111MODULE=on GOBIN=/tmp/bin make
 
-FROM quay.io/prometheus/busybox-linux-amd64:latest
+FROM gcr.io/distroless/static-debian12:nonroot
 
 COPY --from=builder /go/src/github.com/prometheus-community/jiralert/jiralert /bin/jiralert
 

Makefile

@@ -1,4 +1,12 @@
 DOCKER_REPO             ?= quay.io/jiralert
 DOCKER_IMAGE_NAME       ?= jiralert
 
+.PHONY: build
+build:
+	go build -ldflags "-w -s" -a -tags netgo -o jiralert ./cmd/jiralert
+
+.Phone: docker-build
+docker-build:
+	docker buildx build --no-cache --push -t ghcr.io/cloudeteer/jiralert:$$(git rev-parse --short HEAD) --platform linux/arm64,linux/amd64 .
+
 include Makefile.common

pkg/template/template.go

@@ -23,7 +23,6 @@ import (
 	"github.com/go-kit/log"
 	"github.com/go-kit/log/level"
 	"github.com/pkg/errors"
-	"golang.org/x/text/cases"
 )
 
 type Template struct {
@@ -34,7 +33,7 @@ type Template struct {
 var funcs = template.FuncMap{
 	"toUpper": strings.ToUpper,
 	"toLower": strings.ToLower,
-	"title":   cases.Title,
+	"title":   strings.Title, //nolint:staticcheck // TODO(beorn7): Need to come up with a replacement using the cases package.
 	// join is equal to strings.Join but inverts the argument order
 	// for easier pipelining in templates.
 	"join": func(sep string, s []string) string {