SPP docs diff scan web requests feature flag

What does this MR do and why?

Following the merge of !178726 (merged), Web IDE pushes are now able to be diff-scanned.

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doc/user/application_security/secret_detection/secret_push_protection/_index.md

@@ -156,7 +156,7 @@ contain a secret. To instead have only the changes (diff) scanned for secrets wh
 the Git CLI client, enable diff scanning.
 
 To enable diff-only scanning for Web IDE pushes, enable the `secret_checks_for_web_requests feature flag`
-in addition to the spp_scan_diffs feature flag.
+in addition to the `spp_scan_diffs` feature flag.
 
 ## Resolve a blocked push