Drop support for Debian 8

Debian 8 went out of support on June 30, 2020.  Ubuntu 14.04, which uses
the same packages, went out of support in 2019.

Since there's no longer any free security support and we cannot
reasonably be expected to run insecure code in CI, since that's
dangerous to others on the Internet, let's drop support for Debian 8.

docker/run_dockers.bsh

@@ -58,7 +58,7 @@ done
 
 if [[ ${#IMAGES[@]} == 0 ]]; then
   # If you change this list, change script/upload as well.
-  IMAGES=(centos_7 centos_8 debian_8 debian_9 debian_10)
+  IMAGES=(centos_7 centos_8 debian_9 debian_10)
 fi
 
 mkdir -p "${PACKAGE_DIR}"

script/packagecloud.rb

@@ -51,10 +51,6 @@
   # Debian EOL https://wiki.debian.org/LTS/
   # Ubuntu EOL https://wiki.ubuntu.com/Releases
   # Mint EOL https://linuxmint.com/download_all.php
-  "debian/8" => [
-    "debian/jessie",     # EOL June 30, 2020
-    "ubuntu/trusty",     # ESM April 2022
-  ],
   "debian/9" => [
     "debian/stretch",   # EOL June 2022
     "linuxmint/sarah",  # EOL April 2021

script/upload

@@ -187,7 +187,6 @@ Up to date packages are available on [PackageCloud](https://packagecloud.io/gith
 
 [RPM RHEL 7/CentOS 7](https://packagecloud.io/github/git-lfs/packages/el/7/git-lfs-VERSION-1.el7.x86_64.rpm/download)
 [RPM RHEL 8/CentOS 8](https://packagecloud.io/github/git-lfs/packages/el/8/git-lfs-VERSION-1.el8.x86_64.rpm/download)
-[Debian 8](https://packagecloud.io/github/git-lfs/packages/debian/jessie/git-lfs_VERSION_amd64.deb/download)
 [Debian 9](https://packagecloud.io/github/git-lfs/packages/debian/stretch/git-lfs_VERSION_amd64.deb/download)
 [Debian 10](https://packagecloud.io/github/git-lfs/packages/debian/buster/git-lfs_VERSION_amd64.deb/download)