The ubuntu-18.04 runner image is being deprecated

https://github.com/actions/runner-images/issues/6002

.github/workflows/ci_ubuntu_18.04.yml

@@ -1,21 +0,0 @@
-name: ci_ubuntu_18.04
-
-on: [push, pull_request]
-
-jobs:
-  build:
-
-    runs-on: ubuntu-18.04
-
-    steps:
-    - uses: actions/checkout@v3
-    - name: updating available system dependencies
-      run: sudo apt-get update
-    - name: installing system dependencies
-      run: sudo apt-get install -y build-essential pkg-config automake libncurses5-dev autotools-dev libparted-dev dmidecode
-    - name: creating autoconf files
-      run: ./autogen.sh
-    - name: configuring
-      run: ./configure CFLAGS='-O0 -g -Wall -Wextra'
-    - name: compiling
-      run: make