Add Equinox.SqlStreamStore wiring

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The various templates that support >1 database wiring need to have the wiring [which was added to the Equinox repo in the
https://github.com/jet/equinox/blob/master/CHANGELOG.md#2.0.0-rc8 timespan] applied so the command line allows one to nominate ms my or pg as the store alongside es and cosmos - Without looking, I think that's just the equinox-web and equinox-web-csharp templates. eta: eqxBench also needs it

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proProjector supports SqlStreamStore.MsSql as of #74

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This is low priority - if anyone want's to add it, it would appear that oskardudycz/EventSourcing.NetCore#84 is probably the best place to do so (there's no problem with doing it here too, but it's not a priority given the typical person building an app with SqlStreamStore is more interested in doing a bit of legwork and/or considering how stuff puts together relative to people building suites of services in a more established environmentt)