fix(spike protection): correct floor calculation explanation (#13556)

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## DESCRIBE YOUR PR
The [Minimum Event
Calculation](https://docs.sentry.io/pricing/quotas/spike-protection/#minimum-event-calculation)
section hasn't been updated to account for the different minimum floors
for each SKU. `500` is only relevant to errors.

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Author: isabellaenriquez

docs/pricing/quotas/spike-protection.mdx

@@ -81,7 +81,7 @@ As mentioned above, our Spike Protection Algorithm is based on the higher of two
 
 ### Minimum Event Calculation
 
-This calculation, which is the first step of our algorithm, identifies a minimum number of events, using your quota as a guide. This number takes the maximum of either 500 events or the result of the following formula `(3 \* your quota)/(720 \* number of projects)`. The number of projects is capped at 5 and is used to adjust the floor. The equation represents your project using up three times your overall quota in 30 days if events are continually ingested at this hourly rate, thus flagging the project for a potential spike.
+This calculation, which is the first step of our algorithm, identifies a minimum number of events, using your quota as a guide. This number takes the maximum of either 1/10th of the minimum reserved volume quota on the Developer plan for that event type or the result of the following formula: `(3 \* your quota)/(720 \* number of projects)`. The number of projects is capped at 5 and is used to adjust the floor. The equation represents your project using up three times your overall quota in 30 days if events are continually ingested at this hourly rate, thus flagging the project for a potential spike.
 
 ### Usage-Based Calculation