revert ubuntu 21.04 (#174)

* Revert "[1.x] Retrieve php packages from current ubuntu codename for PHP 8.0"

This reverts commit 484b928.

* Revert "retrieve php packages from current ubuntu codename (#171)"

This reverts commit 0df641d.

* Revert "Update to Ubuntu 21.04 (#169)"

This reverts commit d0827fc.

runtimes/7.4/Dockerfile

@@ -1,4 +1,4 @@
-FROM ubuntu:21.04
+FROM ubuntu:20.04
 
 LABEL maintainer="Taylor Otwell"
 
@@ -18,7 +18,7 @@ RUN apt-get update \
     && echo "disable-ipv6" >> ~/.gnupg/dirmngr.conf \
     && apt-key adv --homedir ~/.gnupg --keyserver hkp://keyserver.ubuntu.com:80 --recv-keys E5267A6C \
     && apt-key adv --homedir ~/.gnupg --keyserver hkp://keyserver.ubuntu.com:80 --recv-keys C300EE8C \
-    && echo "deb http://ppa.launchpad.net/ondrej/php/ubuntu hirsute main" > /etc/apt/sources.list.d/ppa_ondrej_php.list \
+    && echo "deb http://ppa.launchpad.net/ondrej/php/ubuntu focal main" > /etc/apt/sources.list.d/ppa_ondrej_php.list \
     && apt-get update \
     && apt-get install -y php7.4-cli php7.4-dev \
        php7.4-pgsql php7.4-sqlite3 php7.4-gd \

runtimes/8.0/Dockerfile

@@ -1,4 +1,4 @@
-FROM ubuntu:21.04
+FROM ubuntu:20.04
 
 LABEL maintainer="Taylor Otwell"
 
@@ -18,7 +18,7 @@ RUN apt-get update \
     && echo "disable-ipv6" >> ~/.gnupg/dirmngr.conf \
     && apt-key adv --homedir ~/.gnupg --keyserver hkp://keyserver.ubuntu.com:80 --recv-keys E5267A6C \
     && apt-key adv --homedir ~/.gnupg --keyserver hkp://keyserver.ubuntu.com:80 --recv-keys C300EE8C \
-    && echo "deb http://ppa.launchpad.net/ondrej/php/ubuntu hirsute main" > /etc/apt/sources.list.d/ppa_ondrej_php.list \
+    && echo "deb http://ppa.launchpad.net/ondrej/php/ubuntu focal main" > /etc/apt/sources.list.d/ppa_ondrej_php.list \
     && apt-get update \
     && apt-get install -y php8.0-cli php8.0-dev \
        php8.0-pgsql php8.0-sqlite3 php8.0-gd \