Remove compatibility with Ubuntu 18.04 (#495)

.github/workflows/molecule.yml

@@ -31,9 +31,6 @@ jobs:
           - distro: ubuntu2004
             tag: latest
             namespace: geerlingguy
-          - distro: ubuntu1804
-            tag: latest
-            namespace: geerlingguy
           - distro: rockylinux8
             tag: latest
             namespace: geerlingguy

.github/workflows/molecule_pgpro.yml

@@ -15,7 +15,6 @@ jobs:
           - centos8
           - debian10
           - debian11
-          - ubuntu1804
           - ubuntu2004
           - ubuntu2204
 

README.md

@@ -148,7 +148,6 @@ _Table of results of daily automated testing of cluster deployment:_
 | Debian 10    | [![GitHub Workflow Status](https://img.shields.io/github/actions/workflow/status/vitabaks/postgresql_cluster/schedule_pg_debian10.yml?branch=master)](https://github.com/vitabaks/postgresql_cluster/actions/workflows/schedule_pg_debian10.yml) |
 | Debian 11    | [![GitHub Workflow Status](https://img.shields.io/github/actions/workflow/status/vitabaks/postgresql_cluster/schedule_pg_debian11.yml?branch=master)](https://github.com/vitabaks/postgresql_cluster/actions/workflows/schedule_pg_debian11.yml) |
 | Debian 12    | [![GitHub Workflow Status](https://img.shields.io/github/actions/workflow/status/vitabaks/postgresql_cluster/schedule_pg_debian11.yml?branch=master)](https://github.com/vitabaks/postgresql_cluster/actions/workflows/schedule_pg_debian12.yml) |
-| Ubuntu 18.04 | [![GitHub Workflow Status](https://img.shields.io/github/actions/workflow/status/vitabaks/postgresql_cluster/schedule_pg_ubuntu1804.yml?branch=master)](https://github.com/vitabaks/postgresql_cluster/actions/workflows/schedule_pg_ubuntu1804.yml) |
 | Ubuntu 20.04 | [![GitHub Workflow Status](https://img.shields.io/github/actions/workflow/status/vitabaks/postgresql_cluster/schedule_pg_ubuntu2004.yml?branch=master)](https://github.com/vitabaks/postgresql_cluster/actions/workflows/schedule_pg_ubuntu2004.yml) |
 | Ubuntu 22.04 | [![GitHub Workflow Status](https://img.shields.io/github/actions/workflow/status/vitabaks/postgresql_cluster/schedule_pg_ubuntu2204.yml?branch=master)](https://github.com/vitabaks/postgresql_cluster/actions/workflows/schedule_pg_ubuntu2204.yml) |
 | CentOS Stream 8 | [![GitHub Workflow Status](https://img.shields.io/github/actions/workflow/status/vitabaks/postgresql_cluster/schedule_pg_centosstream8.yml?branch=master)](https://github.com/vitabaks/postgresql_cluster/actions/workflows/schedule_pg_centosstream8.yml) |

group_vars/all

@@ -15,6 +15,6 @@ os_minimum_versions:
   CentOS: 7
   Rocky: 8.4
   OracleLinux: 7
-  Ubuntu: 18.04
+  Ubuntu: 20.04
   Debian: 10
   AlmaLinux: 8.3

vars/Debian.yml

@@ -31,7 +31,6 @@ os_specific_packages:
   Debian-10: [python, python-dev, python-psycopg2, python-setuptools]
   Debian-11: [python3]  # python 2 is not required
   Debian-12: [python3]  # python 2 is not required
-  Ubuntu-18: [python, python-dev, python-psycopg2, python-setuptools]
   Ubuntu-20: [python3]  # python 2 is not required
   Ubuntu-22: [python3]  # python 2 is not required
 system_packages: