Updated slack image bot preview (fixes #238)

CHANGELOG.md

@@ -11,6 +11,7 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/).
 
 ### Fixed
 - S3 driver file streaming not working properly.
+- Fixed Slack image preview.
 
 ## [3.1.4] - 2020-04-13
 ### Changed

app/helpers.php

@@ -328,8 +328,8 @@ if (!function_exists('isBot')) {
             'curl/',
             'wget/',
             'WhatsApp/',
-            'Slackbot',
-            'Slack-ImgProxy',
+            'Slack',
+            'Twitterbot/',
         ];
 
         foreach ($bots as $bot) {

docs/changelog.md

@@ -16,6 +16,7 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/).
 
 ### Fixed
 - S3 driver file streaming not working properly.
+- Fixed Slack image preview.
 
 ## [3.1.4] - 2020-04-13
 ### Changed