Don't install ext-libev on PHP 7.3

WyriHaximus · WyriHaximus · commit c4e48d76c6f2 · 2018-11-11T22:42:07.000+01:00
diff --git a/travis-init.sh b/travis-init.sh
@@ -30,7 +30,8 @@ if [[ "$TRAVIS_PHP_VERSION" != "hhvm" &&
     # install 'libev' PHP extension (does not support php 7)
     if [[ "$TRAVIS_PHP_VERSION" != "7.0" &&
           "$TRAVIS_PHP_VERSION" != "7.1" &&
-          "$TRAVIS_PHP_VERSION" != "7.2" ]]; then
+          "$TRAVIS_PHP_VERSION" != "7.2"  &&
+          "$TRAVIS_PHP_VERSION" != "7.3" ]]; then
         git clone --recursive https://github.com/m4rw3r/php-libev
         pushd php-libev
         phpize
