[gjs: 1/3] Update Hacking.md

[Philip Chimento <pchimento src gnome org>]

commit 9f3e88e75b03a21d6bcfbcc8d9319bc6537c4bdf
Author: veenanitk <veena nagar 92 gmail com>
Date:   Wed Mar 31 22:50:09 2021 +0000

    Update Hacking.md

 doc/Hacking.md | 1 +
 1 file changed, 1 insertion(+)
---
diff --git a/doc/Hacking.md b/doc/Hacking.md
index 213f8112..f57de05f 100644
--- a/doc/Hacking.md
+++ b/doc/Hacking.md
@@ -23,6 +23,7 @@ libffi, gobject-introspection, and readline.
 
 <details>
     <summary>Ubuntu</summary>
+    <code>sudo apt install meson</code>
     <code>sudo apt-get install libglib2.0-dev libffi-dev libreadline-dev libgirepository1.0-dev</code>
 </details>