update .travis.yml - change used composer version

Author: Flyingmana

.travis.yml

@@ -9,7 +9,9 @@ php:
 
 env:
   - TEST_SUITE=Unit
+    COMPOSER_VERSION=1.9.2
   - TEST_SUITE=Fullstack
+    COMPOSER_VERSION=1.9.2
 
 matrix:
   fast_finish: true
@@ -20,8 +22,6 @@ matrix:
       env: TEST_SUITE=Static
     - php: 7.4
       os: windows
-    - php: 7.4
-      env: COMPOSER_VERSION=1.9.2
     - php: 7.4
       env: COMPOSER_VERSION=dev
   allow_failures: