Update to laravel 7

vendor/symfony/process/InputStream.php

@@ -17,6 +17,8 @@ use Symfony\Component\Process\Exception\RuntimeException;
  * Provides a way to continuously write to the input of a Process until the InputStream is closed.
  *
  * @author Nicolas Grekas <p@tchwork.com>
+ *
+ * @implements \IteratorAggregate<int, string>
  */
 class InputStream implements \IteratorAggregate
 {
@@ -45,7 +47,7 @@ class InputStream implements \IteratorAggregate
             return;
         }
         if ($this->isClosed()) {
-            throw new RuntimeException(sprintf('%s is closed', static::class));
+            throw new RuntimeException(sprintf('"%s" is closed.', static::class));
         }
         $this->input[] = ProcessUtils::validateInput(__METHOD__, $input);
     }
@@ -66,6 +68,10 @@ class InputStream implements \IteratorAggregate
         return !$this->open;
     }
 
+    /**
+     * @return \Traversable<int, string>
+     */
+    #[\ReturnTypeWillChange]
     public function getIterator()
     {
         $this->open = true;