Update GitHub IP ranges for GitHub Enterprise Importer (#56890)

Co-authored-by: Sarita Iyer <[email protected]>

Author: boylejj

data/reusables/enterprise-migration-tool/identifying-githubs-ip-ranges.md

@@ -4,10 +4,10 @@ You'll need to add the following IP ranges to your IP allow list(s):
 * 185.199.108.0/22
 * 140.82.112.0/20
 * 143.55.64.0/20
-* 40.71.233.224/28
+* 135.234.59.224/28 (Note: Introduced July 28, 2025)
 * 2a0a:a440::/29
 * 2606:50c0::/32
-* 20.125.12.8/29 _(active from 00:00 UTC on November 8, 2023)_
+* 20.99.172.64/28 (Note: Introduced July 28, 2025)
 
 You can get an up-to-date list of IP ranges used by {% data variables.product.prodname_importer_proper_name %} at any time with the "Get {% data variables.product.prodname_dotcom %} meta information" endpoint of the REST API.