test(plugin): make expected paths OS-agnostic in installer tests

Build expected paths with filepath.Join so the TestPath assertions pass on Windows as well as Unix.

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

internal/plugin/installer/base_test.go

@@ -34,15 +34,15 @@ func TestPath(t *testing.T) {
 		}, {
 			source:         "https://github.com/jkroepke/helm-secrets",
 			helmPluginsDir: "/helm/data/plugins",
-			expectPath:     "/helm/data/plugins/helm-secrets",
+			expectPath:     filepath.Join("/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",
+			expectPath:     filepath.Join("/helm/data/plugins", "helm-secrets"),
 		}, {
 			source:         "https://github.com/jkroepke/helm-secrets",
 			helmPluginsDir: string(filepath.ListSeparator) + "/helm/data/plugins",
-			expectPath:     "/helm/data/plugins/helm-secrets",
+			expectPath:     filepath.Join("/helm/data/plugins", "helm-secrets"),
 		},
 	}