This test checks that links in hover obey GOPRIVATE.

Requires go1.19+ for the new go/doc/comment package.

-- flags --
-min_go=go1.19

-- env --
GOPRIVATE=mod.com
-- go.mod --
module mod.com
-- p.go --
package p

// T should not be linked, as it is private.
type T struct{} //@hover("T", "T", T)
-- lib/lib.go --
package lib

// GOPRIVATE should also match nested packages.
type L struct{} //@hover("L", "L", L)
-- @L --
```go
type L struct{}
```

GOPRIVATE should also match nested packages.
-- @T --
```go
type T struct{}
```

T should not be linked, as it is private.