ci: retire ubuntu 18.04 from CI

Ubuntu 18.04 is EOL. This change remove it from CI as a follow-up from #4745

Signed-off-by: Manu Bretelle <[email protected]>

.github/workflows/bcc-test.yml

@@ -21,7 +21,7 @@ jobs:
     runs-on: ubuntu-20.04
     strategy:
       matrix:
-        os: [{distro: "ubuntu", version: "18.04", nick: bionic}, {distro: "ubuntu", version: "20.04", nick: focal}]
+        os: [{distro: "ubuntu", version: "20.04", nick: focal}]
         llvm_version: [11, 12, 15]
         env:
         - TYPE: Debug
@@ -33,9 +33,6 @@ jobs:
         - TYPE: Release
           PYTHON_TEST_LOGFILE: critical.log
           RW_ENGINE_ENABLED: ON
-        exclude:
-          - os: {distro: "ubuntu", version: "18.04", nick: bionic}
-            llvm_version: 15
     steps:
     - uses: actions/checkout@v2
     - uses: dorny/paths-filter@v2

.github/workflows/publish-build-containers.yml

@@ -24,7 +24,6 @@ jobs:
     strategy:
       matrix:
         os: [
-          {distro: "ubuntu", version: "18.04", nick: bionic, installed_llvm_versions: "11 12"},
           {distro: "ubuntu", version: "20.04", nick: focal, installed_llvm_versions: "11 12 15"},
           {distro: "fedora", version: "38", nick: "f38", installed_llvm_versions: "this is not used"},
         ]
@@ -41,4 +40,4 @@ jobs:
         os_nick: ${{ matrix.os.nick }}
         llvm_versions: ${{ matrix.os.installed_llvm_versions }}
         password: ${{ secrets.GITHUB_TOKEN }}
-        push: true
+        push: true

docker/build/Dockerfile.ubuntu

@@ -1,10 +1,10 @@
-ARG VERSION="18.04"
+ARG VERSION="20.04"
 FROM ubuntu:${VERSION}
 
 ARG LLVM_VERSION="11"
 ENV LLVM_VERSION=$LLVM_VERSION
 
-ARG SHORTNAME="bionic"
+ARG SHORTNAME="focal"
 
 ARG RUBY_INSTALL_VERSION="0.8.4"
 ENV RUBY_INSTALL_VERSION=$RUBY_INSTALL_VERSION