Whitelist chain exchange topic in lotus

[masih]

Expand the allowed topics in lotus pubusb config to include chain exchange topics. Specifically, there are two cases here:

• Static manifest: /f3/chainexchange/0.0.1/<network-name>
• Dynamic manifest: /f3/chainexchange/0.0.1/<network-name> and all its numerical suffixes similar to what's currently done for f3/granite topic.

This issue is blocked until necessary chain exchange fields are added to manifest for the chain exchange topic name getters to be present, and would consequently needs dependency bubble up in Lotus.

[masih]

This issue is blocked until necessary chain exchange fields are added to manifest for the chain exchange topic name getters to be present, and would consequently needs dependency bubble up in Lotus.

#810 unblocks this.