Provide entries for all columns in datatable columns definitions

Due to a [recent
change](jbox-web/ajax-datatables-rails@0b934f0...81662a8#diff-80d0432c49b2b316f927e4faca3c1a6af69be69fbf98adb7e5b0aa579ca88e87R95)
we need to set all columns used in a datatable in the `@view_columns` map.

src/api/app/datatables/excluded_request_datatable.rb

@@ -11,7 +11,8 @@ def initialize(params, opts = {})
   def view_columns
     @view_columns ||= {
       request: { source: 'BsRequestAction.target_package', cond: :like },
-      description: { source: 'Staging::RequestExclusion.description', cond: :like }
+      description: { source: 'Staging::RequestExclusion.description', cond: :like },
+      actions: {}
     }
   end
 

src/api/app/datatables/maintained_project_datatable.rb

@@ -14,7 +14,8 @@ def initialize(params, opts = {})
 
   def view_columns
     @view_columns ||= {
-      name: { source: 'Project.name', cond: :like }
+      name: { source: 'Project.name', cond: :like },
+      actions: {}
     }
   end
 

src/api/app/datatables/maintenance_incident_datatable.rb

@@ -7,7 +7,13 @@ def initialize(params, opts = {})
   end
 
   def view_columns
-    @view_columns ||= { summary: { source: 'Project.name', orderable: true } }
+    @view_columns ||= {
+      summary: { source: 'Project.name', orderable: true },
+      category: {},
+      packages: {},
+      info: {},
+      release_targets: {}
+    }
   end
 
   # rubocop:disable Naming/AccessorMethodName

src/api/app/datatables/user_configuration_datatable.rb

@@ -6,7 +6,8 @@ def view_columns
     @view_columns ||= {
       name: { source: 'User.login' },
       local_user: { source: 'User.ignore_auth_services', searchable: false },
-      state: { source: 'User.state' }
+      state: { source: 'User.state' },
+      actions: {}
     }
   end