test(plugin): cover install into first HELM_PLUGINS directory

Adds a TestPath case where HELM_PLUGINS contains multiple directories and verifies the plugin installs into the first one.

Signed-off-by: Yuhui Luo <92632263+lyh7c00@users.noreply.github.com>

internal/plugin/installer/base_test.go

@@ -14,6 +14,8 @@ limitations under the License.
 package installer
 
 import (
+	"path/filepath"
+	"strings"
 	"testing"
 
 	"github.com/stretchr/testify/assert"
@@ -33,6 +35,10 @@ func TestPath(t *testing.T) {
 			source:         "https://github.com/jkroepke/helm-secrets",
 			helmPluginsDir: "/helm/data/plugins",
 			expectPath:     "/helm/data/plugins/helm-secrets",
+		}, {
+			source:         "https://github.com/jkroepke/helm-secrets",
+			helmPluginsDir: strings.Join([]string{"/helm/data/plugins", "/helm/data/extra"}, string(filepath.ListSeparator)),
+			expectPath:     "/helm/data/plugins/helm-secrets",
 		},
 	}