Change titles/text on repeating community call events so they don't look like duplicates

[NickleDave]

In #833 @jdamerow and @christophernhill added a repeating event, fixing the calendar so we have community calls alternate Thursdays and Fridays

This works as intended but @cmaimone @exoticDFT noticed that it can look like there are duplicate events, e.g. in this build artifact: https://output.circle-artifacts.com/output/job/65559ca9-11aa-496c-bba3-a9f0279ba5f3/artifacts/0/usrse.github.io/events/index.html

This is true on the live page as of posting this issue (https://us-rse.org/events/) but if you click on them you can see one is the June call on a Friday and the other is July on Thursday.

One solution might be to changed the title / text on the two repeating events so they didn't appear to be repeating.
For example, we could change the title of the original event to be "Bimonthly Community Call on Thursday" and the title of the one that was added to "Bimonthly on Friday" or something like that.

[NickleDave]

Alternatively @exoticDFT wonders if "there is a specific Jekyll way to hide that one file from the event's page, but not the calendar"