Fix OIDC login callback handling on Element Desktop (#33332)

* Fix OIDC login callback handling on Element Desktop

* Add unit tests

* Iterate

* Fix lcov reporter

* Fix coverage paths

* Fix coverage upload

* Ensure `.test.ts` files don't get included in the desktop package

* Fix coverage artifact name

* Delint

* Tidy coverage name

* Improve coverage

apps/desktop/electron-builder.ts

@@ -52,6 +52,7 @@ interface Variant extends Metadata {
 }
 
 type Writable<T> = NonNullable<
+    // eslint-disable-next-line @typescript-eslint/no-unsafe-function-type
     T extends Function ? T : T extends object ? { -readonly [K in keyof T]: Writable<T[K]> } : T
 >;
 
@@ -74,7 +75,7 @@ if (process.env.VARIANT_PATH) {
 }
 
 for (const key in variant) {
-    console.log(`${key}: ${variant[key]}`);
+    console.log(`${key}: ${variant[key as keyof Variant]}`);
 }
 
 interface Configuration extends BaseConfiguration {