ServiceAccounts: Add secret scan service docs (#57926)

* add secret scanning docs

* update docs

* fix merge

* add revoke to docs

* add revoke to docs

* typo fix

* Apply suggestions from code review

Co-authored-by: Christopher Moyer <35463610+chri2547@users.noreply.github.com>

* add step by step instructions

* Apply suggestions from code review

Co-authored-by: Christopher Moyer <35463610+chri2547@users.noreply.github.com>

* Apply suggestions from code review

Co-authored-by: Christopher Moyer <35463610+chri2547@users.noreply.github.com>

* prettier

* Update docs/sources/setup-grafana/configure-security/secret-scan.md

Co-authored-by: Christopher Moyer <35463610+chri2547@users.noreply.github.com>

* feedback

* Update docs/sources/setup-grafana/configure-security/secret-scan.md

* Update docs/sources/setup-grafana/configure-security/secret-scan.md

* Update docs/sources/setup-grafana/configure-security/secret-scan.md

Co-authored-by: Victor Cinaglia <victor@grafana.com>

---------

Co-authored-by: Christopher Moyer <35463610+chri2547@users.noreply.github.com>
Co-authored-by: Victor Cinaglia <victor@grafana.com>

conf/sample.ini

@@ -469,6 +469,22 @@
 # Enter a comma-separated list of users login to hide them in the Grafana UI. These users are shown to Grafana admins and themselves.
 ; hidden_users =
 
+[secretscan]
+# Enable secretscan feature
+;enabled = false
+
+# Interval to check for token leaks
+;interval = 5m
+
+# base URL of the grafana token leak check service
+;base_url = https://secret-scanning.grafana.net
+
+# URL to send outgoing webhooks to in case of detection
+;oncall_url =
+
+# Whether to revoke the token if a leak is detected or just send a notification
+;revoke = true
+
 [service_accounts]
 # Service account maximum expiration date in days.
 # When set, Grafana will not allow the creation of tokens with expiry greater than this setting.