KNOX-2659 - Travis build failure: '/usr/bin/mvn': Operation not permi…

…tted. (#491)

.travis.yml

@@ -29,13 +29,19 @@ matrix:
       group: edge
       os: linux
       dist: focal
-    
+
 env:
   global:
   - DOCKERRUN="docker run --rm -v $PWD:/src -v $HOME/.m2:/root/.m2 -v /var/run/docker.sock:/var/run/docker.sock -w /src"
 services:
   - docker
 before_install:
+  - curl -fsSL https://download.docker.com/linux/ubuntu/gpg | sudo apt-key add -
+  - sudo add-apt-repository "deb [arch=amd64] https://download.docker.com/linux/ubuntu $(lsb_release -cs) stable"
+  - sudo add-apt-repository "deb [arch=arm64] https://download.docker.com/linux/ubuntu $(lsb_release -cs) stable"
+  - sudo apt-get update
+  - sudo apt-get -y -o Dpkg::Options::="--force-confnew" install docker-ce
+  - docker --version
   - lscpu
   - docker pull $IMAGE
 script: