ignore local lsn in wait_cluster_vclock

When waiting for cluster vclock, local component must be ignored because
it's independent on each replica, so the commit fixes corresponding
helper.

test_run.lua

@@ -228,8 +228,11 @@ local function get_cluster_vclock(self, servers)
 end
 
 local function wait_cluster_vclock(self, servers, vclock)
+    -- Ignore local component
+    local wait_vclock = table.deepcopy(vclock)
+    wait_vclock[0] = nil
     for _, name in pairs(servers) do
-        self:wait_vclock(name, vclock)
+        self:wait_vclock(name, wait_vclock)
     end
     return vclock
 end