fix travis error on build package

.travis.yml

@@ -5,6 +5,11 @@ php:
   - 7.2
   - 7.3
 
+install:
+  - echo 'no' | pecl install -f redis
+  - wget https://github.com/swoole/swoole-src/archive/v4.3.4.tar.gz -O swoole.tar.gz && mkdir -p swoole && tar -xf swoole.tar.gz -C swoole --strip-components=1 && rm swoole.tar.gz && cd swoole && phpize && ./configure && make -j$(nproc) && make install && cd -
+  - echo "extension = swoole.so" >> ~/.phpenv/versions/$(phpenv version-name)/etc/php.ini
+
 before_script:
   - composer config -g process-timeout 900 && composer update
   - phpenv config-rm xdebug.ini