I can load multiple files at once by passing multiple paths to the load method, e.g.
load
spark.read .format(\"com.databricks.spark.avro\") .load
load method support varargs type of argument, not the list type. So you have explicitly convert list to varargs adding : _* in load function.
: _*
spark.read.format("com.databricks.spark.avro").load(paths: _*)