Fix reusable build-and-test workflow

Author: t3chguy

.github/workflows/build_desktop_prepare.yaml

@@ -56,6 +56,7 @@ jobs:
             - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6
               with:
                   persist-credentials: false
+                  repository: element-hq/element-web
 
             - uses: pnpm/action-setup@fc06bc1257f339d1d5d8b3a19a8cae5388b55320 # v5
             - uses: actions/setup-node@53b83947a5a98c8d113130e565377fae1a50d02f # v6