Merge pull request ethereum#23083 from karalabe/docker-fix-experimental

travis: enable experimental docker for manifest building

Author: karalabe

.travis.yml

@@ -38,6 +38,8 @@ jobs:
         - docker
       git:
         submodules: false # avoid cloning ethereum/tests
+      before_install:
+        - export DOCKER_CLI_EXPERIMENTAL=enabled
       script:
         - go run build/ci.go docker -image -manifest amd64,arm64 -upload karalabe/geth-docker-test
 
@@ -53,6 +55,8 @@ jobs:
         - docker
       git:
         submodules: false # avoid cloning ethereum/tests
+      before_install:
+        - export DOCKER_CLI_EXPERIMENTAL=enabled
       script:
         - go run build/ci.go docker -image -manifest amd64,arm64 -upload karalabe/geth-docker-test