slack.md: fixed a typo, comma instead of dot

getinvolved/slack.md

@@ -23,7 +23,7 @@ the microbit-community slack channel!
 
 Slack operates it's own [privacy policy](https://slack.com/privacy-policy), so make sure you have read and you agree with this before signing up.
 
-If you'd like to join the slack channel, please fill in the form below. This form collects your email address and system metadata, in accordance with the [privacy policy of Freshdesk](https://www.freshworks.com/privacy/) our support system. We only use this to process an invite to Slack. after which the ticket is closed off and archived. If you wish, you can always [deactivate your slack account at a later date.](https://get.slack.help/hc/en-us/articles/203953146-Deactivate-your-Slack-account)Freshdesk is currently working on the ability to [remove your own data.](https://support.freshdesk.com/support/discussions/topics/14331?page=1). In the meantime, please notify <a href="mailto:help@microbit.org">help@microbit.org</a> if you wish to have your email address removed from the Freshdesk system
+If you'd like to join the slack channel, please fill in the form below. This form collects your email address and system metadata, in accordance with the [privacy policy of Freshdesk](https://www.freshworks.com/privacy/) our support system. We only use this to process an invite to Slack, after which the ticket is closed off and archived. If you wish, you can always [deactivate your slack account at a later date.](https://get.slack.help/hc/en-us/articles/203953146-Deactivate-your-Slack-account)Freshdesk is currently working on the ability to [remove your own data.](https://support.freshdesk.com/support/discussions/topics/14331?page=1). In the meantime, please notify <a href="mailto:help@microbit.org">help@microbit.org</a> if you wish to have your email address removed from the Freshdesk system
 
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