Yarn is available only as yarnpkg command

debian/patches/0710-use-yarnpkg.patch

@@ -0,0 +1,36 @@
+Yarn executable in debian is yarnpkg
+
+--- a/lib/tasks/yarn.rake
++++ b/lib/tasks/yarn.rake
+@@ -2,7 +2,7 @@
+ namespace :yarn do
+   desc 'Ensure Yarn is installed'
+   task :available do
+-    unless system('yarn --version', out: File::NULL)
++    unless system('yarnpkg --version', out: File::NULL)
+       warn(
+         'Error: Yarn executable was not detected in the system.'.color(:red),
+         'Download Yarn at https://yarnpkg.com/en/docs/install'.color(:green)
+@@ -13,10 +13,10 @@
+ 
+   desc 'Ensure Node dependencies are installed'
+   task check: ['yarn:available'] do
+-    unless system('yarn check --ignore-engines', out: File::NULL)
++    unless system('yarnpkg check --ignore-engines', out: File::NULL)
+       warn(
+-        'Error: You have unmet dependencies. (`yarn check` command failed)'.color(:red),
+-        'Run `yarn install` to install missing modules.'.color(:green)
++        'Error: You have unmet dependencies. (`yarnpkg check` command failed)'.color(:red),
++        'Run `yarnpkg install` to install missing modules.'.color(:green)
+       )
+       abort
+     end
+@@ -24,7 +24,7 @@
+ 
+   desc 'Install Node dependencies with Yarn'
+   task install: ['yarn:available'] do
+-    unless system('yarn install --pure-lockfile --ignore-engines')
++    unless system('yarnpkg install --pure-lockfile --ignore-engines')
+       abort 'Error: Unable to install node modules.'.color(:red)
+     end
+   end

debian/patches/series

@@ -30,3 +30,4 @@
 0689-jwt-and-omniauth-google-oauth2.patch
 0690-debian-usage-ping.patch
 0700-add-salsa-link-to-help.patch
+0710-use-yarnpkg.patch