feat: Support for self managed kafka as an event source

[jonife]

Issue #, if available:

Description of changes:
To provide supporting SelfManagedKafka as an event source type in SAM and also provide support for SASL/PLAIN (BASIC_AUTH) as an Auth mechanism.

Description of how you validated changes:
Wrote a couple of tests

Checklist:

• Write/update tests
• make pr passes
• Update documentation

[mgrandis]

Added a few comments

[mgrandis]

Thanks for the extensive test additions!
I think we also want to add:

• unit tests with intrinsic functions
• 1 integration test without intrinsic functions
• 1 integration test with intrinsic functions

We are working on adding tests to other events/resources I think this is needed.
See:

• test: Adding intrinsic tests for Function S3 Event #2100
• test: Added intrinsic tests for Function SNS Event #2101
• feat(Intrinsic Tests): Added Tests for Kinesis Event Source with Intrinsics #2103

[mgrandis]

Thanks for the intrinsic tests!
We still need to see if IP addresses are allowed/supported in KafkaBootstrapServers.

[mgrandis]

The AppVeyor run failed because you added the IP address to the input test templates and not the output ones

[codecov-commenter]

Codecov Report

Merging #2091 (8ee3d81) into develop (e7a1496) will increase coverage by 0.75%.
The diff coverage is 98.19%.

@@             Coverage Diff             @@
##           develop    #2091      +/-   ##
===========================================
+ Coverage    93.58%   94.33%   +0.75%     
===========================================
  Files           90       95       +5     
  Lines         6124     6495     +371     
  Branches      1260     1306      +46     
===========================================
+ Hits          5731     6127     +396     
+ Misses         183      170      -13     
+ Partials       210      198      -12     

Impacted Files	Coverage Δ
samtranslator/model/lambda_.py	93.10% <ø> (ø)
samtranslator/plugins/globals/globals.py	99.05% <ø> (ø)
samtranslator/region_configuration.py	77.77% <63.63%> (-22.23%)	⬇️
samtranslator/translator/translator.py	97.26% <90.00%> (+0.07%)	⬆️
samtranslator/swagger/swagger.py	93.65% <91.89%> (+0.28%)	⬆️
samtranslator/__init__.py	100.00% <100.00%> (ø)
samtranslator/feature_toggle/dialup.py	100.00% <100.00%> (ø)
samtranslator/feature_toggle/feature_toggle.py	100.00% <100.00%> (+12.16%)	⬆️
samtranslator/metrics/method_decorator.py	100.00% <100.00%> (ø)
samtranslator/metrics/metrics.py	100.00% <100.00%> (ø)
... and 25 more

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[CoshUS]

Thanks for the PR. Two small changes.

[CoshUS]

LGTM!

[mgrandis]

Good to go, just a small non blocking change.