web: Safari fixes merge branch (#14181)

* web/admin: Fix layout centering. Adjust theming.

* web: Fix issue where references to Lit SSR break page styles.

* web: Fix issues surrounding color scheme/theme mixup in UI.

web/src/elements/tests/utils.ts

@@ -1,19 +1,20 @@
+import {
+    appendStyleSheet,
+    assertAdoptableStyleSheetParent,
+} from "@goauthentik/common/stylesheets.js";
+
 import { TemplateResult, render as litRender } from "lit";
 
 import AKGlobal from "@goauthentik/common/styles/authentik.css";
 import PFBase from "@patternfly/patternfly/patternfly-base.css";
 
-import { ensureCSSStyleSheet } from "../utils/ensureCSSStyleSheet.js";
-
 // A special version of render that ensures our style sheets will always be available
 // to all elements under test.  Ensures they look right during testing, and that any
 // CSS-based checks for visibility will return correct values.
 
 export const render = (body: TemplateResult) => {
-    document.adoptedStyleSheets = [
-        ...document.adoptedStyleSheets,
-        ensureCSSStyleSheet(PFBase),
-        ensureCSSStyleSheet(AKGlobal),
-    ];
+    assertAdoptableStyleSheetParent(document);
+
+    appendStyleSheet([PFBase, AKGlobal], document);
     return litRender(body, document.body);
 };