Fix migration crash on upgrade from v2.31.0

Removed index definition from Session model since the migration already
creates it. This prevents .sync() from trying to create the index before
migrations run. Also bumped version to 2.34.0 to match migration files.

Fixes: SQLITE_ERROR: no such column: oidcSessionId

package.json

@@ -1,6 +1,6 @@
 {
   "name": "audiobookshelf",
-  "version": "2.32.1",
+  "version": "2.34.0",
   "buildNumber": 1,
   "description": "Self-hosted audiobook and podcast server",
   "main": "index.js",

server/models/Session.js

@@ -76,13 +76,7 @@ class Session extends Model {
       },
       {
         sequelize,
-        modelName: 'session',
-        indexes: [
-          {
-            name: 'sessions_oidc_session_id',
-            fields: ['oidcSessionId']
-          }
-        ]
+        modelName: 'session'
       }
     )