feat: add vendor

vendor/github.com/docker/cli/cli-plugins/manager/suffix_windows.go

@@ -0,0 +1,26 @@
+package manager
+
+import (
+	"path/filepath"
+	"strings"
+
+	"github.com/pkg/errors"
+)
+
+// This is made slightly more complex due to needing to be case insensitive.
+func trimExeSuffix(s string) (string, error) {
+	ext := filepath.Ext(s)
+	if ext == "" {
+		return "", errors.Errorf("path %q lacks required file extension", s)
+	}
+
+	exe := ".exe"
+	if !strings.EqualFold(ext, exe) {
+		return "", errors.Errorf("path %q lacks required %q suffix", s, exe)
+	}
+	return strings.TrimSuffix(s, ext), nil
+}
+
+func addExeSuffix(s string) string {
+	return s + ".exe"
+}