docs: Slack App Directory => Slack Marketplace (#1083)

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# Content

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Author: jayhack

docs/integrations/slack.mdx

@@ -32,8 +32,8 @@ Add the Codegen Slack App to your workspace to enable agent communication.
   icon="slack"
   href="https://codegen.sh/integrations"
 >
-  Install the Codegen app from the Slack App Directory and choose the channels
-  it can access.
+  Install the Codegen app from the Slack Marketplace and choose the channels it
+  can access.
 </Card>
 
 <Note>