Add a vararg interface{} parameter for xrecovery.WithExtraFields

[Aoi-hosizora]

https://github.com/Aoi-hosizora/ahlib-web/blob/8c048957fb02c28892672369e7f02f54cc8cc84c/xrecovery/logger.go#L18-L22

if err := recover(); err != nil {
	rid := c.Writer.Header().Get("X-Request-Id")
	r := result.Error(exception.ServerRecoveryError)
	r.Error = xgin.BuildErrorDto(err, c, skip, true, "request_id", rid)
	xrecovery.WithLogrus(logger, err, xrecovery.WithExtraString(rid), xrecovery.WithExtraFields(map[string]interface{}{"requestID": rid}))
	r.JSON(c)
}

[Aoi-hosizora]

Also a function used for converting from []interface{} to map[string]interface{} can be added to ahlib.xslice. (Done)

[Aoi-hosizora]

Done in 8a863de.