tests: introduce dummy_server_init and use it in all journald fuzzers
    
    (cherry picked from commit ed62712dc6fb236845c489a7f386c7aff0ec31d6)
    
    Resolves: #1764560
    
    patch_name: 0261-tests-introduce-dummy_server_init-and-use-it-in-all-.patch
    present_in_specfile: true
    location_in_specfile: 261
    squash_commits: true