cmd/go: add a test for -sectcreate in LDFLAGS

It was already covered by a regex pattern, but it didn't have a test.

To fix the issue for good, added regression test.

Fixes #28832.

Change-Id: I861e3bed92d3b9484fd8671270dbd2e264b10d2d
Reviewed-on: https://go-review.googlesource.com/c/go/+/191311
Reviewed-by: Daniel Martí <mvdan@mvdan.cc>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Daniel Martí <mvdan@mvdan.cc>
TryBot-Result: Gobot Gobot <gobot@golang.org>

src/cmd/go/internal/work/security_test.go

@@ -143,6 +143,7 @@ var goodLinkerFlags = [][]string{
 	{"-L", "framework"},
 	{"-framework", "Chocolate"},
 	{"-v"},
+	{"-Wl,-sectcreate,__TEXT,__info_plist,${SRCDIR}/Info.plist"},
 	{"-Wl,-framework", "-Wl,Chocolate"},
 	{"-Wl,-framework,Chocolate"},
 	{"-Wl,-unresolved-symbols=ignore-all"},