[varnish] update lts image to 6.0.7

[gquintard]

This one is a bit more than the usual switch to a more recent package, it also trade stretch for buster, since the former is EOL.

I don't know if there are special announcements (I'll post on the Vanrish mailing list), tagging or something like that to do here, if so, please let me know!

[github-actions]

Diff for dac7949:

diff --git a/_bashbrew-cat b/_bashbrew-cat
index db4e8c9..2fde20d 100644
--- a/_bashbrew-cat
+++ b/_bashbrew-cat
@@ -1,8 +1,8 @@
 Maintainers: Guillaume Quintard <guillaume@varni.sh> (@gquintard)
 GitRepo: https://github.com/varnish/docker-varnish.git
 
-Tags: 6.0, 6.0.6-1, 6.0.6, stable
-GitCommit: 2459369407fbf77df75d6948ee48de8c814fb3e4
+Tags: 6.0, 6.0.7-1, 6.0.7, stable
+GitCommit: c0846f15b04cd499a1df1fb62f0693b41a84e636
 Directory: stable/debian
 
 Tags: 6.5, 6.5.1-1, 6.5.1, 6, latest, fresh
diff --git a/_bashbrew-list b/_bashbrew-list
index 0d95462..d4f3fa4 100644
--- a/_bashbrew-list
+++ b/_bashbrew-list
@@ -1,7 +1,7 @@
 varnish:6
 varnish:6.0
-varnish:6.0.6
-varnish:6.0.6-1
+varnish:6.0.7
+varnish:6.0.7-1
 varnish:6.5
 varnish:6.5.1
 varnish:6.5.1-1
diff --git a/varnish_stable/Dockerfile b/varnish_stable/Dockerfile
index dbeaa0a..5d0f692 100644
--- a/varnish_stable/Dockerfile
+++ b/varnish_stable/Dockerfile
@@ -1,6 +1,6 @@
-FROM debian:stretch-slim
+FROM debian:buster-slim
 
-ENV VARNISH_VERSION 6.0.6-1~stretch
+ENV VARNISH_VERSION 6.0.7-1~buster
 ENV VARNISH_SIZE 100M
 
 RUN set -ex; \
@@ -16,7 +16,7 @@ RUN set -ex; \
 	gpg --batch --export export $key > /etc/apt/trusted.gpg.d/varnish.gpg; \
 	gpgconf --kill all; \
 	rm -rf $GNUPGHOME; \
-	echo deb https://packagecloud.io/varnishcache/varnish60lts/debian/ stretch main > /etc/apt/sources.list.d/varnish.list; \
+	echo deb https://packagecloud.io/varnishcache/varnish60lts/debian/ buster main > /etc/apt/sources.list.d/varnish.list; \
 	apt-get update; \
 	apt-get install -y --no-install-recommends varnish=$VARNISH_VERSION; \
 	apt-get purge -y --auto-remove -o APT::AutoRemove::RecommendsImportant=false $fetchDeps; \

[tianon]

I don't know if there are special announcements (I'll post on the Vanrish mailing list), tagging or something like that to do here, if so, please let me know!

We typically only worry about it in cases where there might be breaking changes (like docker-library/postgres#582) and/or it's common for users to be FROM the image (and install more stuff), which is why images like python and golang often have multiple variants like x.y-buster vs x.y-stretch. I'm guessing neither of those apply here?

[gquintard]

We should be fine, there's a jemalloc upgrade, but it that had been an issue, I'm sure somebody would have reported it on the fresh variants of the image. Go ahead!

[gquintard]

@tianon , can I attract your attention to #8674 while I have you?