Merge #10566: [docs] Use the "domain name setup" image (previously unused) in the gitian docs

7631066 Use the "domain name setup" image (previously unused) in the gitian docs (practicalswift)

Tree-SHA512: 747f3afa15dd6007076fb20d5fd16e20e2fb920c5eea5557664ddd42bd2c52e1a517124a649e3d1605fcc9e0c06a567c63b1023dda22f813a2d331b28097baa0

Author: laanwj

doc/gitian-building.md

@@ -131,6 +131,7 @@ To select a different button, press `Tab`.
   - Leave domain name empty.
 
 ![](gitian-building/debian_install_5_configure_the_network.png)
+![](gitian-building/debian_install_6_domain_name.png)
 
 - Choose a root password and enter it twice (remember it for later)