[ci] Ignore INTERNAL from GetConnectedSynchronizers mid-reconnect

[ray-roestenburg-da]

Canton fails the whole call when one synchronizer has no topology client during the remove/add window in SynchronizerRegistryHelpers. See https://github.com/DACH-NY/cn-test-failures/issues/9445

(this is just the ignore, I'll try a fix in canton for the actual issue)

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