Move coveralls execution to latest-env

Use stable version of php-coveralls

Author: Koopzington

.travis.yml

@@ -40,13 +40,13 @@ matrix:
         - DEPS=lowest
     - php: 5.6
       env:
-        - EXECUTE_TEST_COVERALLS=true
         - DEPS=locked
         - DEPLOY_DOCS="$(if [[ $TRAVIS_BRANCH == 'master' && $TRAVIS_PULL_REQUEST == 'false' ]]; then echo -n 'true' ; else echo -n 'false' ; fi)"
         - PATH="$HOME/.local/bin:$PATH"
     - php: 5.6
       env:
         - DEPS=lastest
+        - EXECUTE_TEST_COVERALLS=true
     - php: 7
       env:
         - DEPS=lowest
@@ -75,7 +75,7 @@ notifications:
 before_install:
   - if [[ $EXECUTE_TEST_COVERALLS != 'true' ]]; then phpenv config-rm xdebug.ini || return 0 ; fi
   - composer self-update
-  - if [[ $EXECUTE_TEST_COVERALLS == 'true' ]]; then composer require --dev satooshi/php-coveralls ; fi
+  - if [[ $EXECUTE_TEST_COVERALLS == 'true' ]]; then composer require --dev satooshi/php-coveralls:^1.0 ; fi
 
 install:
   - if [[ $DEPS == 'latest' ]]; then travis_retry composer update $COMPOSER_ARGS ; fi