Added ppa with testing tool, including g++11

Author: madduci

.github/workflows/build.yaml

@@ -38,7 +38,7 @@ jobs:
           # Note: tags has to be all lower-case
           tags: |
             madduci/docker-linux-cpp:latest
-            madduci/docker-linux-cpp:1.7
+            madduci/docker-linux-cpp:1.8
           # build on feature branches, push only on master branch
           push: ${{ github.ref == 'refs/heads/master' }}
 

install_compilers.sh

@@ -4,6 +4,7 @@ readonly DEBIAN_PACKAGES="${1}"
 readonly CLANG_PACKAGES="${2}"
 
 DEBIAN_FRONTEND=noninteractive
+add-apt-repository -y ppa:ubuntu-toolchain-r/test \
 apt-get update
 
 echo "Installing ${DEBIAN_PACKAGES}"