update travis.yml to use 8.8 & 8.9 version of Drupal

Author: WengerK

.travis.yml

@@ -8,17 +8,19 @@ language: php
 sudo: false
 
 php:
-  - 7
-  - 7.1
-  - 7.2
+  - 7.3
 
 services:
   - mysql
 
 matrix:
-  fast_finish: true
-  allow_failures:
-    - php: hhvm
+  include:
+    - name: D8.8
+      env: DRUPAL_TI_RUNNERS="phpunit-core" DRUPAL_TI_CORE_BRANCH="8.8.x" DRUPAL_TI_PHPUNIT_ARGS="--group template_whisperer"
+    - name: D8.9
+      env: DRUPAL_TI_RUNNERS="phpunit-core" DRUPAL_TI_CORE_BRANCH="8.9.x" DRUPAL_TI_PHPUNIT_ARGS="--group template_whisperer"
+    - name: D9.0
+      env: DRUPAL_TI_RUNNERS="phpunit-core" DRUPAL_TI_ENVIRONMENT="drupal-9" DRUPAL_TI_CORE_BRANCH="9.0.x" DRUPAL_TI_PHPUNIT_ARGS="--group template_whisperer"
 
 env:
   global:
@@ -39,8 +41,11 @@ env:
     # The environment to use, supported are: drupal-7, drupal-8
     - DRUPAL_TI_ENVIRONMENT="drupal-8"
 
-    # Switch to 8.6.x versions instead of 8.1.x by default.
-    - DRUPAL_TI_CORE_BRANCH="8.6.x"
+    # The drush version to use, by default: drush/drush:8.0.*
+    - DRUPAL_TI_DRUSH_VERSION="drush/drush:^10.1.1"
+
+    # Switch to 8.9.x versions instead of 8.1.x by default.
+    - DRUPAL_TI_CORE_BRANCH="8.9.x"
 
     # The installation profile to use:
     #- DRUPAL_TI_INSTALL_PROFILE="testing"
@@ -71,6 +76,7 @@ env:
     - DRUPAL_TI_BEHAT_BROWSER="firefox"
 
     # PHPUnit specific commandline arguments.
+    - DRUPAL_TI_PHPUNIT_VERSION="^7.0"
     - DRUPAL_TI_PHPUNIT_ARGS=""
     # Specifying the phpunit-core src/ directory is useful when e.g. a vendor/
     # directory is present in the module directory, which phpunit would then
@@ -106,16 +112,15 @@ mysql:
 before_install:
   - composer self-update
   - cd ./tests
-  - composer global require "lionsad/drupal_ti:1.*"
+  - composer global config repositories.repo-name git https://github.com/wengerk/drupal_ti
+  - composer global require "lionsad/drupal_ti:dev-add-drupal-9-support"
   - drupal-ti before_install
 
 install:
   - drupal-ti install
 
 before_script:
   - drupal-ti before_script
-  # Update from PHPUnit 4.x to 6.x as required by Drupal 8.6.x.
-  - composer run-script drupal-phpunit-upgrade --working-dir=/home/travis/build/antistatique/drupal-8/drupal --no-interaction
 
 script:
   # Disable deprecations helper to avoid build failed caused by usage of