feat: add monitoring guide (#1147)

* feat: add monitoring guide

* Update monitoring.md

Signed-off-by: Justine Geffen <justinegeffen@users.noreply.github.com>

---------

Signed-off-by: Justine Geffen <justinegeffen@users.noreply.github.com>
Co-authored-by: Justine Geffen <justinegeffen@users.noreply.github.com>

Author: gavinelder

platform-enterprise_docs/enterprise-sidebar.json

@@ -95,7 +95,8 @@
               "enterprise/advanced-topics/custom-launch-container",
               "enterprise/advanced-topics/firewall-configuration",
               "enterprise/advanced-topics/seqera-container-images",
-              "enterprise/advanced-topics/content-security-policy"
+              "enterprise/advanced-topics/content-security-policy",
+              "enterprise/advanced-topics/monitoring"
             ]
           },
           "enterprise/general_troubleshooting"