feat: adds displayName property to OIDC authentication module (#6096)

* Adds displayName property to oidc authentication method
* fix: update displayName prop
* fix: use blank display name in oidc auth

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Co-authored-by: Nicolas Giard <github@ngpixel.com>

server/modules/authentication/oidc/authentication.js

@@ -28,7 +28,8 @@ module.exports = {
             providerKey: req.params.strategy,
             profile: {
               ...profile,
-              email: _.get(profile, '_json.' + conf.emailClaim)
+              email: _.get(profile, '_json.' + conf.emailClaim),
+              displayName: _.get(profile, conf.displayNameClaim, ''),
             }
           })
           if (conf.mapGroups) {