issue#3939 : Allow client authentication from pulsar-flink package (#3949)

Problem:
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pulsar-flink module (aka flink connector) internally uses pulsar-client. Though the pulsar client allows setting tokens in the client builder, the flink connector does not provide a way to pass authentication token to the pulsar client it uses internally.

Solution:
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Accept authetication information as an input in pulsar-flink module. Pass this authentication information to pulsar-client.
17 files changed