maintner/maintnerd: install tini via apt

The keyserver used in the installation of tini is no longer supported.
This change installs tini via apt.

Fixes golang/go#48095

Change-Id: I7360952fc48ce08b4a2bb7d6120b266a5cfb8181
Reviewed-on: https://go-review.googlesource.com/c/build/+/346411
Trust: Carlos Amedee <carlos@golang.org>
Run-TryBot: Carlos Amedee <carlos@golang.org>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Alexander Rakoczy <alex@golang.org>
diff --git a/maintner/maintnerd/Dockerfile b/maintner/maintnerd/Dockerfile
index 2e0b1a1..e90b41b 100644
--- a/maintner/maintnerd/Dockerfile
+++ b/maintner/maintnerd/Dockerfile
@@ -2,7 +2,7 @@
 # Use of this source code is governed by a BSD-style
 # license that can be found in the LICENSE file.
 
-FROM golang:1.13 AS build
+FROM golang:1.16 AS build
 LABEL maintainer "golang-dev@googlegroups.com"
 
 ENV GO111MODULE=on
@@ -36,20 +36,15 @@
 # For interacting with the Go source & subrepos
 RUN apt-get update && apt-get install -y \
 	--no-install-recommends \
-	ca-certificates netbase \
+	ca-certificates \
+	dirmngr \
 	git-core \
+	gnupg \
+	netbase \
 	openssh-client \
-	gnupg dirmngr \
+	tini \
 	&& rm -rf /var/lib/apt/lists/*
 
-# See https://github.com/golang/go/issues/23705
-ENV TINI_VERSION v0.16.1
-ADD https://github.com/krallin/tini/releases/download/${TINI_VERSION}/tini /tini
-ADD https://github.com/krallin/tini/releases/download/${TINI_VERSION}/tini.asc /tini.asc
-RUN gpg --keyserver hkp://p80.pool.sks-keyservers.net:80 --recv-keys 595E85A6B1B4779EA4DAAEC70B588DFF0527A9B7 \
- && gpg --verify /tini.asc
-RUN chmod +x /tini
-
 # Add Github.com's known_hosts entries, so git push calls later don't
 # prompt, and don't need to have their strict host key checking
 # disabled.
@@ -60,4 +55,4 @@
 	&& chmod 0600 ~/.ssh/known_hosts
 
 COPY --from=build /go/bin/maintnerd /
-ENTRYPOINT ["/tini", "--", "/maintnerd"]
+ENTRYPOINT ["/usr/bin/tini", "--", "/maintnerd"]
diff --git a/maintner/maintnerd/deployment-prod.yaml b/maintner/maintnerd/deployment-prod.yaml
index 4dcd9e2..8b9f3fa 100644
--- a/maintner/maintnerd/deployment-prod.yaml
+++ b/maintner/maintnerd/deployment-prod.yaml
@@ -21,7 +21,7 @@
       - name: maintnerd
         image: gcr.io/symbolic-datum-552/maintnerd:latest
         imagePullPolicy: Always
-        command: ["/tini", "--", "/maintnerd", "--config=go", "--bucket=golang-maintner-log", "--verbose", "--data-dir=/cache", "--listen=:80", "--autocert=maintner.golang.org", "--autocert-bucket=golang-maintner-autocert"]
+        command: ["/usr/bin/tini", "--", "/maintnerd", "--config=go", "--bucket=golang-maintner-log", "--verbose", "--data-dir=/cache", "--listen=:80", "--autocert=maintner.golang.org", "--autocert-bucket=golang-maintner-autocert"]
         volumeMounts:
         - mountPath: /cache
           name: pv-maintner-cache