add Bartłomiej as committer (#20896)
add Bartłomiej as committer (#20896)

Signed-off-by: Sheng Zha <fd9da504b63c1736e52a84ae954da2a315f2f28a@amazon.com>
DickJC123/mxnet,apache/incubator-mxnet,apache/incubator-mxnet,DickJC123/mxnet,DickJC123/mxnet,apache/incubator-mxnet,DickJC123/mxnet,apache/incubator-mxnet