Fixed issues found from tests

app/Exceptions/BookStackExceptionHandlerPage.php

@@ -0,0 +1,42 @@
+<?php
+
+namespace BookStack\Exceptions;
+
+use Illuminate\Contracts\Foundation\ExceptionRenderer;
+
+class BookStackExceptionHandlerPage implements ExceptionRenderer
+{
+    public function render($throwable)
+    {
+        return view('errors.debug', [
+            'error'       => $throwable->getMessage(),
+            'errorClass'  => get_class($throwable),
+            'trace'       => $throwable->getTraceAsString(),
+            'environment' => $this->getEnvironment(),
+        ])->render();
+    }
+
+    protected function safeReturn(callable $callback, $default = null)
+    {
+        try {
+            return $callback();
+        } catch (\Exception $e) {
+            return $default;
+        }
+    }
+
+    protected function getEnvironment(): array
+    {
+        return [
+            'PHP Version'       => phpversion(),
+            'BookStack Version' => $this->safeReturn(function () {
+                $versionFile = base_path('version');
+
+                return trim(file_get_contents($versionFile));
+            }, 'unknown'),
+            'Theme Configured' => $this->safeReturn(function () {
+                return config('view.theme');
+            }) ?? 'None',
+        ];
+    }
+}