Adjust rate-limiting to webhook executions per plan

Release notes

Problem to solve

In #330133 (closed), introduced limits per plan for webhooks but only configured a webhook rate-limit for the Free tier.

We have to analyze the data we have to find good limits per each plan. Similar to what we did for the free tier #330133 (comment 590024134).

Proposal

Set limits for paid tiers but would need higher limits. We already use plan-based limits so this is simple to add, we just need to determine suitable limits for each tier. We should analyze what normal, non-abuse patterns look like today and what other similar services have set as limits.

This issue represents the first iteration where we log if a customer would be over limit but do not enforce the limit. A second issue #365605 (closed) will enforce the limit.

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Availability & Testing

There is an issue for expanding rate limit tests

Suggestion: This issue should be brought into the milestone, with an addition of a EE specific unit/controller test that will trigger or not trigger the rate limit in different circumstances.