ci: update travis ci

.travis.yml

@@ -49,7 +49,7 @@ script:
 
 after_success:
   - if [[ "$CC" == "gcc" && "$CODE_COVERAGE" == "ON" ]]; then
-      pip install --user cpp-coveralls
+      pip install --user cpp-coveralls && 
       coveralls
         --build-root .
         --exclude lib