Cancellation probe D: remove broken test

internal/globals/ci_gate_probe_test.go

@@ -1,9 +0,0 @@
-package globals
-
-import "testing"
-
-// Scratch-branch probe: a deliberately failing test used to verify that CI
-// actually executes the test stage. Never merged.
-func TestCIGateRunsTests(t *testing.T) {
-	t.Fatal("deliberate failure: the CI gate must report this commit red")
-}