pages*: change manpages.ubuntu.com to manned.org (#14048)

pages/linux/check-language-support.md

@@ -1,7 +1,7 @@
 # check-language-support
 
 > Display a list of missing language packages on Ubuntu.
-> More information: <https://manpages.ubuntu.com/manpages/latest/man1/check-language-support.html>.
+> More information: <https://manned.org/check-language-support>.
 
 - Display a list of missing language packages based on installed software and enabled locales:
 

pages/linux/do-release-upgrade.md

@@ -1,7 +1,7 @@
 # do-release-upgrade
 
 > The Ubuntu release upgrader.
-> More information: <https://ubuntu.com/server/docs/upgrade-introduction>.
+> More information: <https://manned.org/do-release-upgrade.8>.
 
 - Upgrade to the latest release:
 

pages/linux/pro.md

@@ -1,7 +1,7 @@
 # pro
 
 > Manage Ubuntu Pro services.
-> More information: <https://manpages.ubuntu.com/manpages/latest/man1/ubuntu-advantage.1.html>.
+> More information: <https://manned.org/ubuntu-advantage.1>.
 
 - Connect your system to the Ubuntu Pro support contract:
 

pages/linux/virt-manager.md

@@ -1,7 +1,7 @@
 # virt-manager
 
 > A desktop user interface for managing KVM and Xen virtual machines and LXC containers.
-> More information: <https://manpages.ubuntu.com/manpages/man1/virt-manager.1.html>.
+> More information: <https://manned.org/virt-manager.1>.
 
 - Launch the GUI: