Skip psalm on PHP 7.0

Author: paragonie-security

.github/workflows/ci.yml

@@ -24,7 +24,7 @@ jobs:
           tools: psalm, phpunit:${{ matrix.phpunit-versions }}
 
       - name: Install dependencies
-        run: composer self-update; composer install
+        run: composer self-update; composer remove --dev vimeo/psalm; composer install
 
       - name: PHPUnit tests
         run: vendor/bin/phpunit