Add Sh_binaries property

The sh_binary module is not supported the vendor variant. So, even if
there is "vendor: true" in sh_binary module, the image variant is
"image:" instead of "image:vendor.Tiramisu".
But the vendor APEX has vendor variant, so vendor APEX module and
sh_binary module have different variants and the sh_binary cannot be
added to vendor apex.
So the Sh_binaries property is added, and the image variant is removed
at DepsMutator.

Bug: 205065320
Test: make -j40 && sh_binary is added to vendor APEX && install check
Change-Id: I30e2d96a73b45e7b06eff24550542cb010008c41

apex/apex_test.go

@@ -4248,7 +4248,7 @@ func TestApexWithShBinary(t *testing.T) {
 		apex {
 			name: "myapex",
 			key: "myapex.key",
-			binaries: ["myscript"],
+			sh_binaries: ["myscript"],
 			updatable: false,
 		}