Remove build 60 steps

This test is already covered in the individual graph driver tests and it
adds 15s to the test run without adding value.  The original idea was to
test max number of layers, this is fulfilled by the graph drivers.

Signed-off-by: Michael Crosby <crosbymichael@gmail.com>

integration-cli/docker_cli_build_test.go

@@ -661,27 +661,6 @@ RUN ls -le /file`
 
 }
 
-func (s *DockerSuite) TestBuildSixtySteps(c *check.C) {
-	testRequires(c, DaemonIsLinux) // TODO Windows: This test passes on Windows,
-	// but currently adds a disproportionate amount of time for the value it has.
-	// Removing it from Windows CI for now, but this will be revisited in the
-	// TP5 timeframe when perf is better.
-	name := "foobuildsixtysteps"
-
-	ctx, err := fakeContext("FROM "+minimalBaseImage()+"\n"+strings.Repeat("ADD foo /\n", 60),
-		map[string]string{
-			"foo": "test1",
-		})
-	if err != nil {
-		c.Fatal(err)
-	}
-	defer ctx.Close()
-
-	if _, err := buildImageFromContext(name, ctx, true); err != nil {
-		c.Fatal(err)
-	}
-}
-
 func (s *DockerSuite) TestBuildAddSingleFileToRoot(c *check.C) {
 	testRequires(c, DaemonIsLinux) // Linux specific test
 	name := "testaddimg"