[ZT] Hyperlint: Fix broken anchor in link (#18316)

Co-authored-by: hyperlint-ai[bot] <154288675+hyperlint-ai[bot]@users.noreply.github.com>

Author: hyperlint-ai[bot]

src/content/docs/cloudflare-one/identity/devices/service-providers/custom.mdx

@@ -114,7 +114,7 @@ To create a custom service-to-service integration:
 7. In **Polling frequency**, choose how often Cloudflare Zero Trust should query the external API for information.
 8. Select **Test and save**. The test checks if Cloudflare can authenticate to the API URL using the provided Access credentials.
 
-Next, [configure a device posture check](#configure-the-posture-check) to determine if a given posture score constitutes a pass or fail.
+Next, [configure a device posture check](#4-configure-the-posture-check) to determine if a given posture score constitutes a pass or fail.
 
 ### 4. Configure the posture check