[MM-39597] Implement ConfigDiffs.Sanitize() (#18855)

* Implement ConfigDiffs.Sanitize()

* Remove possibly sensitive info from logs

api4/config_local.go

@@ -73,7 +73,7 @@ func localUpdateConfig(c *Context, w http.ResponseWriter, r *http.Request) {
 		c.Err = model.NewAppError("updateConfig", "api.config.update_config.diff.app_error", nil, diffErr.Error(), http.StatusInternalServerError)
 		return
 	}
-	auditRec.AddMeta("diff", diffs)
+	auditRec.AddMeta("diff", diffs.Sanitize())
 
 	newCfg.Sanitize()
 
@@ -131,7 +131,7 @@ func localPatchConfig(c *Context, w http.ResponseWriter, r *http.Request) {
 		c.Err = model.NewAppError("patchConfig", "api.config.patch_config.diff.app_error", nil, diffErr.Error(), http.StatusInternalServerError)
 		return
 	}
-	auditRec.AddMeta("diff", diffs)
+	auditRec.AddMeta("diff", diffs.Sanitize())
 
 	auditRec.Success()