Merge ~ubuntu-docker-images/ubuntu-docker-images/+git/templates:remove-focal-refs into ~ubuntu-docker-images/ubuntu-docker-images/+git/templates:master

[Sergio Durigan Junior]

This commit aims to make the templates fully generic, by removing the (few) references to Focal that are still present in them.

I tested it by re-generating Apache2's README.md and HACKING.md and checking that everything works as expected.

Arguably, the "distroversion" manipulation that I've added to the README_DOCKERHUB.md template is a bit fragile in the sense that it requires the "base" parameter to always have the Ubuntu release number there, and not its name, but I don't foresee a situation where we will deviate from this, so I think it's fine.

[Sergio Durigan Junior (sergiodj)]

You will see that there is an extra hunk at the end of the diff. My Emacs is configured to always insert a newline at the end of the file, that's why it's there.

[Lucas Kanashiro (lucaskanashiro)]

LGTM, +1.

review: Approve

diff --git a/templates/HACKING_deb.md b/templates/HACKING_deb.md
index 64678bb..37e3398 100644
--- a/templates/HACKING_deb.md
+++ b/templates/HACKING_deb.md
@@ -1,7 +1,7 @@
 # Contributing
 
 In Ubuntu, ${application} is available as a `.deb` package.  For this reason,
-this image was built by installing the ${application} Ubuntu Focal package
+this image was built by installing the ${application} ${base} package
 inside a docker container.
 
 In order to contribute to the ${application} OCI image, do the following:
diff --git a/templates/README_DOCKERHUB.md b/templates/README_DOCKERHUB.md
index 6e2a318..c05871a 100644
--- a/templates/README_DOCKERHUB.md
+++ b/templates/README_DOCKERHUB.md
@@ -3,7 +3,8 @@
 Current ${application} Docker Image from Ubuntu. Receives security updates and rolls to newer ${application} or Ubuntu LTS. This repository is exempted from per-user rate limits. For [LTS Docker Image](https://ubuntu.com/security/docker-images) versions of this image, see `lts/${repo}`. 
 <%
     baserepo='ubuntu'
-    pretag=version.split(".")[0]+'.'+version.split(".")[1]+'-20.04_' 
+    distroversion=base.strip('Ubuntu').strip('LTS').lstrip().rstrip()
+    pretag=version.split(".")[0]+'.'+version.split(".")[1]+'-'+distroversion+'_'
     tag=pretag+'beta'
 %>
 <%include file="header.md" args="tag=tag, pretag=pretag, baserepo=baserepo, **locals()['pageargs']"/>
diff --git a/templates/README_DOCKERHUB_LTS.md b/templates/README_DOCKERHUB_LTS.md
index 109a888..4ae13f0 100644
--- a/templates/README_DOCKERHUB_LTS.md
+++ b/templates/README_DOCKERHUB_LTS.md
@@ -4,7 +4,8 @@
 The [LTS Docker Image Portfolio](https://ubuntu.com/security/docker-images) are consistent, compliant, minimal and secure images with Extended Security Maintenance (ESM) commitments from Canonical. This repository is exempted from per-user rate limits.
 <%
     baserepo='lts'
-    pretag=version.split(".")[0]+'.'+version.split(".")[1]+'-20.04_' 
+    distroversion=base.strip('Ubuntu').strip('LTS').lstrip().rstrip()
+    pretag=version.split(".")[0]+'.'+version.split(".")[1]+'-'+distroversion+'_'
     tag=pretag+'beta'
 %>
 <%include file="header.md" args="tag=tag, pretag=pretag, baserepo=baserepo, **locals()['pageargs']"/>
@@ -21,4 +22,4 @@ The [LTS Docker Image Portfolio](https://ubuntu.com/security/docker-images) are 
 ## Usage
 
 If your usage includes redistribution, please [contact Canonical](https://ubuntu.com/security/docker-images#get-in-touch).
-<%include file="common_usage.md" args="tag=tag, pretag=pretag, baserepo=baserepo, **locals()['pageargs']"/>
\ No newline at end of file
+<%include file="common_usage.md" args="tag=tag, pretag=pretag, baserepo=baserepo, **locals()['pageargs']"/>