pkg/reference: remove deprecated SplitObject

Signed-off-by: Sebastiaan van Stijn <github@gone.nl>

pkg/reference/reference_test.go

@@ -192,33 +192,3 @@ func TestReferenceParser(t *testing.T) {
 		})
 	}
 }
-
-func BenchmarkSplitObject(b *testing.B) {
-	inputs := []string{
-		"",
-		"@",
-		"docker.io@",
-		"@digest",
-		"docker.io/library/redis:foo?fooo=asdf",
-		"docker.io/library/redis:foo@sha256:abcdef?fooo=asdf",
-		"docker.io/library/redis@sha256:abcdef?fooo=asdf",
-		"docker.io/library/redis:obj@abcdef?fooo=asdf",
-		"localhost:5000/library/redis:obj@abcdef?fooo=asdf",
-		"/docker.io/library/redis:obj@abcdef?fooo=asdf",
-		"docker.io/library/redis?fooo=asdf",
-		"sub-dom1.foo.com/bar/baz/quux:latest",
-		"sub-dom1.foo.com/bar/baz/quux:some-long-tag",
-		"b.gcr.io/test.example.com/my-app:test.example.com",
-		"xn--n3h.com/myimage:xn--n3h.com", // ☃.com in punycode
-		"xn--7o8h.com/myimage:xn--7o8h.com@sha512:fffffff",
-		"http://xn--7o8h.com/myimage:xn--7o8h.com@sha512:fffffff",
-	}
-
-	b.ReportAllocs()
-
-	for i := 0; i < b.N; i++ {
-		for _, input := range inputs {
-			_, _ = SplitObject(input)
-		}
-	}
-}