update Ogmios version in nightly workflow.

Author: KtorZ

.github/workflows/network-synchronization.yaml

@@ -16,7 +16,7 @@ jobs:
     strategy:
       matrix:
         network: [ preview ]
-        ogmios_version: [ v6.11.0 ]
+        ogmios_version: [ v7.0.0 ]
         cardano_node_version: [ 11.0.1 ]
 
     runs-on: ubuntu-latest