Update website community page to mention fortnightly triage meeting

[jmhbnz]

Recently we started a fortnightly triage meeting for the etcd project that re-uses our standard fortnightly community meeting zoom details but just occurs on alternate weeks to the main community meeting.

We should update our website community and triage pages to mention the new meeting:

• https://etcd.io/community
• https://etcd.io/docs/v3.6/triage/issues
• https://etcd.io/docs/v3.5/triage/issues

These files are located under content/en/community and content/en/docs in the repo, lets update them to advertise and ensure we get as many people along to our fortnightly triage meeting as possible.

[mjlshen]

I can help with this

[nate-double-u]

Hi @mjlshen, thanks for helping out!