[WAF] Update malicious uploads example (#21360)

Author: pedrosousa

src/content/docs/waf/detections/malicious-uploads/example-rules.mdx

@@ -40,10 +40,10 @@ This custom rule example blocks requests addressed at `/upload` with uploaded co
 
 This custom rule example blocks requests with uploaded content objects over 15 MB in size (the current content scanning limit):
 
-- Expression: `any(cf.waf.content_scan.obj_sizes[*] >= 15000000)`
+- Expression: `any(cf.waf.content_scan.obj_sizes[*] >= 15728640)`
 - Action: _Block_
 
-In this example, you must also test for equality because currently any file over 15 MB will be handled internally as if it had a size of 15 MB. This means that using the `>` (greater than) [comparison operator](/ruleset-engine/rules-language/operators/#comparison-operators) would not work for this particular rule — you should use `>=` (greater than or equal) instead.
+In this example, you must also test for equality because currently any file over 15 MB will be handled internally as if it had a size of 15 MB (15,728,640 bytes). This means that using the `>` (greater than) [comparison operator](/ruleset-engine/rules-language/operators/#comparison-operators) would not work for this particular rule — you should use `>=` (greater than or equal) instead.
 
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