run Cross Compiles workflow on self-hosted runner

Reviewed-by: Hugo Landau <hlandau@openssl.org>
Reviewed-by: Tomas Mraz <tomas@openssl.org>
(Merged from #23042)

(cherry picked from commit 625287b)

.github/workflows/cross-compiles.yml

@@ -148,7 +148,7 @@ jobs:
             tests: none
           }
         ]
-    runs-on: ubuntu-latest
+    runs-on: ${{ github.server_url == 'https://github.com' && 'ubuntu-latest' || 'ubuntu-22.04-self-hosted' }}
     steps:
     - name: install package repository
       if: matrix.platform.ppa != ''