Improve backwards compatability for the TLS transfer parser

[torben-hansen]

Description of changes:

Allows the parser to deserialise TLS transfer state as long as the state version is as old or older than the parser.

#1322 added a few more (optional) fields to the TLS transfer format. We want this to impose a version bump. But the parser currently doesn't allow inputting state serialised through an older parser. Improve backwards compatibility to allow future version bumps.

This makes deploying to a large fleet with a long delta of software versions being out-of-sync much easier.

By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license and the ISC license.

[skmcgrail]

Still need to bump SSL_SERIAL_VERSION to version 2 right? Maybe I didn't understand our discussion outcome earlier, but I thought that was the intent of the follow-up was to bump and handle the backwards compatibility with the older version?

[torben-hansen]

Still need to bump SSL_SERIAL_VERSION to version 2 right? Maybe I didn't understand our discussion outcome earlier, but I thought that was the intent of the follow-up was to bump and handle the backwards compatibility with the older version?

I could bump it or just leave it as-is. There is no functional difference. I left it out in this PR with no real arguments for why.

[torben-hansen]

Still need to bump SSL_SERIAL_VERSION to version 2 right? Maybe I didn't understand our discussion outcome earlier, but I thought that was the intent of the follow-up was to bump and handle the backwards compatibility with the older version?

bumped config parser version: ed630ee

[codecov-commenter]

Codecov Report

Attention: 4 lines in your changes are missing coverage. Please review.

Comparison is base (f3e49b0) 76.47% compared to head (4348543) 76.47%.

Files	Patch %	Lines
ssl/ssl_transfer_asn1.cc	63.63%	4 Missing ⚠️

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #1337   +/-   ##
=======================================
  Coverage   76.47%   76.47%           
=======================================
  Files         421      421           
  Lines       71016    71021    +5     
=======================================
+ Hits        54308    54312    +4     
- Misses      16708    16709    +1     

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