Modify .travis.yml file

Author: lin777

.travis.yml

@@ -18,16 +18,7 @@ before_script:
   - sleep 3 # give xvfb some time to start
   - "java -Dwebdriver.chrome.driver=chromedriver -jar selenium-server-standalone-3.14.0.jar -port 4444 > /tmp/seleniumlog.&"
 smalltalk:
-  - Pharo64-alpha
-  - Pharo-alpha
-  - Pharo64-7.0
-  - Pharo64-6.1
   - Pharo-6.1
-  - Pharo-5.0
-  - Squeak-5.1
-  - GemStone-3.3.3
-  - GemStone-3.2.15
-  - GemStone-3.1.0.6
 matrix:
   allow_failures:
     - smalltalk: Pharo64-alpha