fix: deprecate extra field to avoid confusion (#777)

PiperOrigin-RevId: 477776089
Source-Link: googleapis/googleapis@57062cd
Source-Link: https://github.com/googleapis/googleapis-gen/commit/99b76b52b138a79277fcac8c46644b815c7a37d7
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protos/google/privacy/dlp/v2/dlp.proto

@@ -5292,9 +5292,8 @@ message InfoTypeSummary {
   // The infoType.
   InfoType info_type = 1;
 
-  // Approximate percentage of non-null rows that contained data detected by
-  // this infotype.
-  int32 estimated_prevalence = 2;
+  // Not populated for predicted infotypes.
+  int32 estimated_prevalence = 2 [deprecated = true];
 }
 
 // Infotype details for other infoTypes found within a column.