Fix route naming

Jellyfin.Api/Controllers/SubtitleController.cs

@@ -196,7 +196,7 @@ namespace Jellyfin.Api.Controllers
         /// <param name="startPositionTicks">The start position of the subtitle in ticks.</param>
         /// <response code="200">File returned.</response>
         /// <returns>A <see cref="FileContentResult"/> with the subtitle file.</returns>
-        [HttpGet("Videos/{itemId}/{mediaSourceId}/Subtitles/{index}/Stream.{routeFormat}")]
+        [HttpGet("Videos/{routeItemId}/routeMediaSourceId/Subtitles/{routeIndex}/Stream.{routeFormat}")]
         [ProducesResponseType(StatusCodes.Status200OK)]
         [ProducesFile("text/*")]
         public async Task<ActionResult> GetSubtitle(