Fix typo

a space was missing

(cherry picked from commit 4026e53)

Author: johanrhodin

release-notes/3.8.29.md

@@ -21,7 +21,7 @@ what package repositories and tools can be used to provision modern Erlang versi
 See the [Upgrading guide](https://www.rabbitmq.com/upgrade.html) for general documentation on upgrades and
 [RabbitMQ change log](https://www.rabbitmq.com/changelog.html) for release notes of other releases.
 
-If upgrading from a`3.7.x` release, see [3.8.0 release notes](https://github.com/rabbitmq/rabbitmq-server/releases/tag/v3.8.0)
+If upgrading from a `3.7.x` release, see [3.8.0 release notes](https://github.com/rabbitmq/rabbitmq-server/releases/tag/v3.8.0)
 upgrade and compatibility notes first.
 
 If upgrading from a `3.6.x` or older [release series](https://www.rabbitmq.com/versions.html), first upgrade