Update .travis.yml

Update ELM_VERSION to 0.19.1 and add `elm-format` as a check.
Updated travis ubuntu version to focal.

DEBUGGING

Author: Leonardo Barcaroli

.travis.yml

@@ -1,25 +1,24 @@
 sudo: false
 
+dist: focal
 language: node_js
 node_js: node
 
 cache:
   directories:
-    - elm-stuff/build-artifacts
-    - elm-stuff/packages
     - sysconfcpus
 os:
   - linux
 
-env: ELM_VERSION=0.19.0
+env: ELM_VERSION=0.19.1
 
 before_install:
   - echo -e "Host github.com\n\tStrictHostKeyChecking no\n" >> ~/.ssh/config
 
 install:
   - node --version
   - npm --version
-  - npm install -g elm@$ELM_VERSION elm-test@0.19.0-beta4
+  - npm install elm@$ELM_VERSION elm-test@$ELM_VERSION [email protected]
   # Faster compile on Travis.
   - |
     if [ ! -d sysconfcpus/bin ];
@@ -32,4 +31,5 @@ install:
     fi
 
 script:
-  - $TRAVIS_BUILD_DIR/sysconfcpus/bin/sysconfcpus -n 2 elm-test
+  - $TRAVIS_BUILD_DIR/sysconfcpus/bin/sysconfcpus -n 2 ./node_modules/.bin/elm-test --compiler $TRAVIS_BUILD_DIR/node_modules/.bin/elm-test/elm
+  - $TRAVIS_BUILD_DIR/sysconfcpus/bin/sysconfcpus -n 2 ./node_modules/.bin/elm-format --validate .