[feat] Support end-to-end encryption in C Reader API

[rbarbey]

Fixes #166 and is a prerequisite for apache/pulsar-client-node#276

Motivation

This change allows C and derived clients to use end-to-end encryption for Readers.

Modifications

Exposed the methods that already in the C++ API in the C interface

Verifying this change

• Make sure that the change passes the CI checks.

This change is a trivial rework / code cleanup without any test coverage.

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[shibd]

Nice work! Can you fix the code format and add a unit test?

[rbarbey]

@shibd Thank you for the feedback! I've fixed the formatting and wrote a very basic test for the reader config C API, much like the one for the consumer configuration.

If this PR gets approved, is there any chance to still get this into the 3.2.0 release (saw the voting thread on the dev mailing list)? This would be really great since my ultimate goal is address apache/pulsar-client-node#276

[shibd]

@shibd Thank you for the feedback! I've fixed the formatting and wrote a very basic test for the reader config C API, much like the one for the consumer configuration.

If this PR gets approved, is there any chance to still get this into the 3.2.0 release (saw the voting thread on the dev mailing list)? This would be really great since my ultimate goal is address apache/pulsar-client-node#276

/cc @BewareMyPower I think we should include it on the 3.2.0 release.