FSharpType.Format drops qualifier namespaces that are parent in the context

[auduchinok]

FSharpType.Format drops parent namespaces when the type being formatted and context have a common parent namespace.

namespace Ns1.Ns2

type T() = class end

Formatting T via FSharpType.Format in Ns1.Ns3 context:

Expected:

namespace Ns1.Ns3

Ns1.Ns2.T

Actual:

namespace Ns1.Ns3

Ns2.T // produces error

It should only skip qualifier namespaces when they are actually opened or are the same namespace as the context.

In addition to FSharpType.Format usages in tooling, it likely affects generating things in the compiler, e.g. signature files generation.