Prefer lowest require update

Author: gmazzap

.github/workflows/php-qa.yml

@@ -35,7 +35,7 @@ jobs:
               run: find ./src/ ./tests/src/ ./tests/cases/ -type f -name '*.php' -print0 | xargs -0 -L 1 -P 4 -- php -l
 
             - name: Install dependencies
-              run: composer install -q -n -a --no-progress --prefer-dist${{ matrix.prefer }}${{ matrix.ignore-platform }}
+              run: composer update -q -n -a --no-progress --prefer-dist${{ matrix.prefer }}${{ matrix.ignore-platform }}
 
             - name: Run unit tests (>= 7.3)
               if: ${{ matrix.php >= 7.3 }}