Going from failing tests to failing tests is not a regression

-- p_test.go --
package p

import "testing"

func TestX(t *testing.T) {
	t.FailNow()
}

-- .commit --
Initial commit (with failing test)

-- p_test.go --
package p

import "testing"

func TestX(t *testing.T) {
	t.FailNow()
}

-- .commit --
Test still failing

-- .run_test --
OK