Tracking issue for Generic Associated Types support

[mchernyavsky]

This should be reconsidered/reprioritized with this blog post in mind: https://blog.rust-lang.org/2021/08/03/GATs-stabilization-push.html

• Update inspections for Type Aliase ANN: Update inspections for Type Aliases #7976
• Render generic parameters for associated types in Implement Members REF: Render generic parameters for associated types in Implement Members #7977
• Parse of generic parameters for assoc types / type aliases and assoc type bindings GRAM: parse of generic parameters for assoc types / type aliases and assoc type bindings #8542
• Basic type inference for GATs TY: Basic type inference for GATs #8544
• Render generic parameters for assoc types if any UI: Render generic parameters for assoc types if any #8565
• Support new where clause location for associated types GRAM&ANN: Support new where clause location for associated types #8826
• Wrong type inference with GATs Wrong type inference with GATs #9896
• Generic with associated types complains perfectly compilable code #10293