Update .travis.yml

Author: cryptiklemur

.travis.yml

@@ -56,7 +56,6 @@ matrix:
         - env: STABILITY="dev"
 
 before_install:
-    - yes '' | pecl install memcache
     - if [[ $COVERAGE != true ]]; then phpenv config-rm xdebug.ini || true; fi
     - if ! [ -z "$STABILITY" ]; then composer config minimum-stability ${STABILITY}; fi;
     - if ! [ -v "$DEPENDENCIES" ]; then composer require --no-update ${DEPENDENCIES}; fi;