feat(dropped data): Dropped data is only filtered by project and time (#20243)

## DESCRIBE YOUR PR

Updating doc to reflect that dropped data is only filtered by project
and time.

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## PRE-MERGE CHECKLIST

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- [ ] Checked Vercel preview for correctness, including links
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Co-authored-by: Shannon Anahata <shannonanahata@gmail.com>
Co-authored-by: Cursor <cursoragent@cursor.com>

Author: 3 people

docs/product/explore/dropped-data.mdx

@@ -13,6 +13,8 @@ When data is ingested into Sentry, it can be dropped intentionally or unintentio
 ## Troubleshooting Dropped Data
 Traces, Logs, and Application Metrics charts in [Explore](/product/explore/) can show data that Sentry did not store. Hover over the dropped data line at the bottom of the chart to see the summary. Click on the line to see the details and troubleshoot.
 
+**Note: The dropped data you see on your chart, and in the details list, is only filtered by time and project.**
+
 The dropped data line leaves out data you chose to drop: everything in [Client Sampled](#category-client-sampled) and [Inbound Filters](#category-inbound-filters), plus [Disallowed Origin](#disallowed-origin), [Missing Signature](#missing-signature), and [DSN Rate Limit](#dsn-rate-limit). These reasons still appear in the details list.
 
 Below are all the possible reasons why data might be dropped. They correspond with the title you will see when exploring dropped data in Sentry.