Make unhandled webhook events return 200 instead of 501

[nickmisasi]

Summary

Zoom sends webhooks for various reasons. The Mattermost Zoom Plugin only handles meeting.ended events. For all others, a 501 - Not Implemented status code is returned. Zoom expects a 200 or 204 response, otherwise it assumes the delivery failed and it will try again at a future time. This means that by returning a 501, Zoom will re-queue the webhook to be sent again - exasperating the issue.

This has been causing us to go over alert thresholds in the Community mattermost server due to it being a 5xx error. My proposal here is to simply return a 200 in the event we don't care about a specific webhook, so that Zoom marks the delivery as successful and doesn't attempt further.

Ticket Link

n/a

[codecov]

Codecov Report

Merging #257 (b8735c3) into master (8a5a54d) will not change coverage.
The diff coverage is 0.00%.

@@          Coverage Diff           @@
##           master    #257   +/-   ##
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  Coverage    0.00%   0.00%           
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  Files           8       8           
  Lines         900     900           
======================================
  Misses        900     900           

Impacted Files	Coverage Δ
server/http.go	0.00% <0.00%> (ø)

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[stylianosrigas]

LGTM

[mickmister]

@nickmisasi Looks like we have an extra event configured for our Zoom instance Participant/Host joined meeting. I've removed this event just now, so we shouldn't be seeing this occur anymore in the meantime.

Thanks for implementing this fix 👍

[dipak-demansol]

@mickmister You removed Qa review label but still my name is there in the review list so could you pls tell me, should i test it or not?

[mickmister]

@dipak-demansol The change was trivial enough that I deemed it good to merge without QA testing