fix(test): strip colour codes before looking for the lint skip notice (CI run 8937)

Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>

test/lintgate/lintgate_test.go

@@ -10,6 +10,7 @@ import (
 	"os"
 	"os/exec"
 	"path/filepath"
+	"regexp"
 	"strings"
 	"testing"
 )
@@ -40,10 +41,13 @@ func scratchModule(t *testing.T) string {
 	return dir
 }
 
+// ansi matches the colour escape sequences task prints when it thinks it has a terminal.
+var ansi = regexp.MustCompile("\x1b\\[[0-9;]*m")
+
 // hasSkipNotice reports whether the skip notice was printed as output. Task echoes the command
 // line first, and that line contains the same words, so a substring match would be vacuous.
 func hasSkipNotice(out string) bool {
-	for _, line := range strings.Split(out, "\n") {
+	for _, line := range strings.Split(ansi.ReplaceAllString(out, ""), "\n") {
 		if strings.HasPrefix(line, "golangci-lint not installed") {
 			return true
 		}