Support TLS max size when encrypted

[joeljfischer]

Fixes #1954

Risk

This PR makes no API changes.

Testing Plan

• I have verified that I have not introduced new warnings in this PR (or explain why below)
• I have run the unit tests with this PR
• I have tested this PR against Core and verified behavior (if applicable, if not applicable, explain why below).

Unit Tests

Tests were added for sending encryption RPCs when encryption is ready and not ready.

Core Tests

• Tested normal non-encrypted use-case
• Tested encryption use-case using an encryption test app to send a one-frame PutFile over encryption.
• Tested encryption use-case using an encryption test app to send a 15-frame PutFile over encryption.
• Tested encryption use-case using an encryption test app to receive a 3-frame OnSystemRequest over encryption

Core version / branch / commit hash / module tested against: Core v7.1.0
HMI name / version / branch / commit hash / module tested against: Generic HMI v0.10.0, sdl_hmi v5.5.0

Summary

Updates encryption to only send a max of 16384 bytes per packet due to TLS limitations when connected over encryption.

• See Implement multiframe encryption correctly sdl_java_suite#1644 for the comparable Java Suite PR.

Changelog

Bug Fixes

• Fix encrypted multi-frame messages being too large and failing to send.

Tasks Remaining:

• Update unit tests
• Smoke Test

CLA

• I have signed the CLA

[codecov]

Codecov Report

Merging #1955 (5e0d3c1) into hotfix/7.1.1 (1fa7c01) will decrease coverage by 69.48%.
The diff coverage is 64.78%.

❗ Current head 5e0d3c1 differs from pull request most recent head 6f55654. Consider uploading reports for the commit 6f55654 to get more accurate results

@@                Coverage Diff                @@
##           hotfix/7.1.1    #1955       +/-   ##
=================================================
- Coverage         83.69%   14.21%   -69.49%     
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  Files               441      441               
  Lines             22564    22577       +13     
=================================================
- Hits              18885     3209    -15676     
- Misses             3679    19368    +15689     

[NicoleYarroch]

Some small changes requested