Add audit log to logout all sessions (#62)

## Description

- [x] Adding audit log to logout all sessions
- [x] Updating variable name 

AB#1437807

## Motivation and Context

Audit log for logout all sessions

## How Has This Been Tested?

Locally integrated with PICS. Used webhook to receive the audit entry.

## Checklist:

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that apply. -->
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- [x] My change requires a change to the documentation or CHANGELOG.
- [x] I have updated the documentation/CHANGELOG accordingly.
- [x] I have created a feature (non-master) branch for my PR.

oauthproxy.go

@@ -363,7 +363,7 @@ func (p *OAuthProxy) buildProxySubrouter(s *mux.Router) {
 			p.SignOut(w, r, false)
 		},
 	))
-	s.Path(picsSignOutAllDevicesPath).Handler(p.sessionChain.ThenFunc(
+	s.Path(picsSignOutAllSessionsPath).Handler(p.sessionChain.ThenFunc(
 		func(w http.ResponseWriter, r *http.Request) {
 			p.SignOut(w, r, true)
 		},
@@ -813,6 +813,8 @@ func (p *OAuthProxy) backendLogout(rw http.ResponseWriter, req *http.Request, si
 		if resp.StatusCode() != 200 {
 			logger.Errorf("error while calling backend logout url, returned error code %v", resp.StatusCode())
 		}
+
+		p.picsAuditClient.CreateSuccessfulLogoutAuditEntry(session, req.RequestURI, req.Header.Get("edisp-org-id"))
 	} else {
 		if providerData.BackendLogoutURL == "" {
 			return

pics_oauthproxy.go

@@ -11,7 +11,7 @@ import (
 )
 
 const (
-	picsSignOutAllDevicesPath = "/sign_out_all_sessions"
+	picsSignOutAllSessionsPath = "/sign_out_all_sessions"
 )
 
 func PicsSignOutAllSessions(backendLogoutAllSessionsURL string, introspectClaims string, accessToken string) (resp requests.Result, err error) {

pkg/pics/audit/audit_client.go

@@ -69,6 +69,7 @@ func (c *Client) CreateSuccessfulLogoutAuditEntry(ss *sessions.SessionState, app
 		System: "http://hl7.org/fhir/ValueSet/audit-event-type", Version: "1", Code: "110123", Display: "Logout", UserSelected: "All Sessions"}
 	c.createAuditEntry(ss, appURL, tenantID, "0", "Success", &coding)
 }
+
 func (c *Client) createAuditEntry(ss *sessions.SessionState, appURL string, tenantID string, outcomeCode string, outcomeDesc string, coding *Coding) {
 	if !c.enabled {
 		return