just disable psalm caching

.travis.yml

@@ -10,6 +10,5 @@ before_script:
   - composer install
 
 script:
-  - vendor/bin/psalm --clear-cache
   - composer build
 

composer.json

@@ -16,7 +16,7 @@
         "lint": "@php ./vendor/bin/parallel-lint --exclude vendor/ --exclude lib/block_random_int.php .",
         "test": "@php ./vendor/bin/phpunit tests/",
         "test-fixup": "mkdir -p templates_c ; test -f config.local.php || touch config.local.php",
-        "psalm": "@php ./vendor/bin/psalm --show-info=false "
+        "psalm": "@php ./vendor/bin/psalm --no-cache --show-info=false "
     },
     "require": {
         "php": ">=5.2"