add a failing test to check the build fails

test/ci_tests/01_basic/basic_spec.lua

@@ -2,6 +2,9 @@ require("cURL")
 
 describe("civetweb basic", function()
  it("should serve a simple get request", function()
-   assert.is(true)
+   assert.is_true(true)
+ end)
+ it("should fail the build on a failed test", function()
+   assert.is_false(true)
  end)
 end)