[Windows Server 2016] Memory Leak when using TLS

## Bug Report

**Describe the bug**
Our Windows Servers getting unresponsive after a while due to high memory consumption in the Non-Paged Memory Pool. To narrow down the issue only a `dummy` input and a `forward` output using TLS is needed. I run one instance without tls and one with tls=on to compare it's memory consumption.

**To Reproduce**
- run `fluent-bit.exe -i dummy -p rate=10000 -o forward -p -p tls=on`
- and compare it's memory consumption without tls enabled.

**Expected behavior**
The Memory consumption should not grow when tls enabled.

**Screenshots**

**Your Environment**
* Version used: 2.0.6
* Configuration: `fluent-bit.exe -i dummy -p rate=10000 -o forward -p -p tls=on`
* Operating System and version: Windows Server 2016

**Additional context**
The leak might got introduced in version 2.x, it is not present in 1.9.10
We found the leak initially in 2.0.5, the provided improvements in the TLS part of 2.0.6 made it actually a bit better.

Let me know if you need more infos

Reproduce the issue on Windows Server 2016 with the documented fluent-bit.exe dummy input and forward output, comparing tls=on with TLS disabled. Monitor non-paged pool memory at the reported rate of 10000 and compare versions 2.0.6 and 1.9.10; done means memory does not continually grow with TLS enabled.

Written by the indexing model from the issue text.