Version 3.21.0

• #963 [TASK] Update Domain Pricing
• #959 [FEATURE] Extend internal customer contact api
• #958 [BUGFIX] Fix partial authentication error with status tabs
• #961 [BUGFIX] Fix TypeError when creating new network interface
• #952 [BUGFIX] Prevent creation of zombie processes under certain conditions
• #941 [BUGFIX] Prevent hidden usage bars when usage is below 1%
• #950 [BUGFIX] Update on-premise pricing for V9 Servers
• #943 [FEATURE] Add attack mode

Reference: #957