Discard inlinability check.

This was only useful as a design research expedition.

It's here in history if you want to refer to it.

node/basic/inlinability/inlinability_test.go

-// Compile with '-gcflags -S' and grep the assembly for `"".Test`.
-// You'll find that both methods produce identical bodies modulo line numbers.
-package inlinability
-
-import (
-	"testing"
-
-	ipld "github.com/ipld/go-ipld-prime"
-	basicnode "github.com/ipld/go-ipld-prime/node/basic"
-)
-
-var sink ipld.NodeBuilder
-
-func TestStructReference(t *testing.T) {
-	nb := basicnode.Style__String{}.NewBuilder()
-	sink = nb
-}
-
-func TestVarReference(t *testing.T) {
-	nb := basicnode.Style.String.NewBuilder()
-	sink = nb
-}