Update warning message

As requested on aosp/1975486

Fixes: 217248902
Test: Presubmits
Change-Id: I14e65722d8ab96125827d34e8501b4a518a27b57
diff --git a/mk2rbc/node.go b/mk2rbc/node.go
index 2fa6a85..5d98d7b 100644
--- a/mk2rbc/node.go
+++ b/mk2rbc/node.go
@@ -101,7 +101,7 @@
 func (i inheritedDynamicModule) emitSelect(gctx *generationContext) {
 	if i.needsWarning {
 		gctx.newLine()
-		gctx.writef("%s.mkwarning(%q, %q)", baseName, i.location, "Including a path with a non-constant prefix, please convert this to a simple literal to generate cleaner starlark. See https://source.android.com/setup/build/bazel/product_config/issues/includes for details.")
+		gctx.writef("%s.mkwarning(%q, %q)", baseName, i.location, "Please avoid starting an include path with a variable. See https://source.android.com/setup/build/bazel/product_config/issues/includes for details.")
 	}
 	gctx.newLine()
 	gctx.writef("_entry = {")