upgrade to laravel 7 and set branch to v2

vendor/nikic/php-parser/lib/PhpParser/Node/Expr/ShellExec.php

@@ -1,30 +0,0 @@
-<?php declare(strict_types=1);
-
-namespace PhpParser\Node\Expr;
-
-use PhpParser\Node\Expr;
-
-class ShellExec extends Expr
-{
-    /** @var array Encapsed string array */
-    public $parts;
-
-    /**
-     * Constructs a shell exec (backtick) node.
-     *
-     * @param array $parts      Encapsed string array
-     * @param array $attributes Additional attributes
-     */
-    public function __construct(array $parts, array $attributes = []) {
-        $this->attributes = $attributes;
-        $this->parts = $parts;
-    }
-
-    public function getSubNodeNames() : array {
-        return ['parts'];
-    }
-    
-    public function getType() : string {
-        return 'Expr_ShellExec';
-    }
-}