chore: update README.md

Author: actions-user

README.md

@@ -96,7 +96,7 @@ No providers.
 | Name | Source | Version |
 |------|--------|---------|
 | <a name="module_default_label"></a> [default\_label](#module\_default\_label) | cloudposse/label/null | 0.25.0 |
-| <a name="module_notify_slack"></a> [notify\_slack](#module\_notify\_slack) | terraform-aws-modules/notify-slack/aws | 6.4.0 |
+| <a name="module_notify_slack"></a> [notify\_slack](#module\_notify\_slack) | terraform-aws-modules/notify-slack/aws | 6.7.0 |
 | <a name="module_this"></a> [this](#module\_this) | cloudposse/label/null | 0.25.0 |
 
 ## Resources