[libadwaita/wip/exalm/flatpak-docs-typo] doc: Fix a typo

[Alexander Mikhaylenko <alexm src gnome org>]

commit b082f7120cf27fc735e5ae29c2be1ced8499012e
Author: Alexander Mikhaylenko <alexm gnome org>
Date:   Tue Dec 21 14:24:20 2021 +0500

    doc: Fix a typo

 doc/build-howto.md | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
---
diff --git a/doc/build-howto.md b/doc/build-howto.md
index c3beb52f..503d5ee3 100644
--- a/doc/build-howto.md
+++ b/doc/build-howto.md
@@ -28,7 +28,7 @@ of the package name.
 If you're using the GNOME SDK of the version 42 or later, Libadwaita is already
 included and there's no need to do anything.
 
-If you're using an older version of a different SDK, add the following modules
+If you're using an older version or a different SDK, add the following modules
 to your manifest:
 
 ```json