The policies arranged by the RFU for registered clubs are public and employers liability and personal accident cover. These policies do not provide cover in respect of the commercial impact of a pandemic like Coronavirus.
If a club has a business/commercial/property policy it is possible that the business interruption section of that may provide some cover, depending on the policy wording. If you have a query regarding your business policy, you should refer to your insurer or broker and the RFU arranged policies.