Dynamically link to local OpenSSL version

[QAQJ]

Description of changes: This is an example code for dynamically linking to the OpenSSL in your OS, instead of statically link it with the downloaded version. This can be helpful if you want to make sure the KPL is FIPS compliant.

Steps to build it (using a RHEL docker image as an example):

1. docker run -ti redhat/ubi8 /bin/bash
2. yum install -y git make wget gcc gcc-c++ perl cmake libstdc++-static.x86_64 libuuid-devel.x86_64 maven java-11-openjdk-devel.x86_64
3. [Optional] For my docker image, there was no pre-installed OpenSSL, so I have to download one to reproduce the customer scenario: yum install openssl-devel
   1. In my case, the paths are

$ whereis openssl
openssl: /usr/bin/openssl /usr/include/openssl /usr/share/man/man1/openssl.1ssl.gz

3. git clone https://github.com/awslabs/amazon-kinesis-producer.git
4. make the code change in this PR
5. Copy and pasted your AWS credential, since a unit test will use it
6. build it by running ./bootstrap.sh
   1. In the output you can find an output message

-- OpenSSL include dir: /usr/include
-- OpenSSL libraries: /usr/lib64/libssl.so;/usr/lib64/libcrypto.so
-- OpenSSL version: 1.1.1k

Which is outputted by CMAKE file, which shows that the we are using the OpenSSL version pre-installed in your OS.

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