Update project setup.

Signed-off-by: crynobone <crynobone@gmail.com>

Author: crynobone

.scrutinizer.yml

@@ -1,5 +1,5 @@
 before_commands:
-    - 'composer install --prefer-source --no-interaction'
+    - 'composer install --prefer-dist --no-interaction'
 filter:
     paths:
         - 'src/*'

.travis.yml

@@ -14,7 +14,6 @@ env:
     - coverage=no
 
 before_script:
-  - travis_retry composer self-update
   - composer config discard-changes true
   - if [[ $setup = 'basic' ]]; then travis_retry composer install --prefer-dist --no-interaction; fi
   - if [[ $setup = 'stable' ]]; then travis_retry composer update --prefer-dist --no-interaction --prefer-stable; fi