doc(library/type_context): relax preconditions for using `is_def_eq` in new implementation
doc(library/type_context): relax preconditions for using `is_def_eq` in new implementation

fpvandoorn/lean,leodemoura/lean,Kha/lean,leodemoura/lean,dselsam/lean,leanprover/lean,dselsam/lean,dselsam/lean,leanprover-community/lean,digama0/lean,Kha/lean,leodemoura/lean,fpvandoorn/lean,Kha/lean,leanprover-community/lean,Kha/lean,leodemoura/lean,leodemoura/lean,leanprover-community/lean,fpvandoorn/lean,fpvandoorn/lean,leanprover/lean,leanprover/lean,dselsam/lean,Kha/lean,leanprover/lean,fpvandoorn/lean,leanprover-community/lean,leodemoura/lean,leanprover/lean,Kha/lean,digama0/lean,digama0/lean,digama0/lean,digama0/lean,digama0/lean,leanprover/lean,leanprover-community/lean,dselsam/lean,leanprover-community/lean,dselsam/lean,fpvandoorn/lean