Add SASL authentication for kafka acquisition

[acm-073]

This PR implements #3336
At the moment, only the "PLAIN" SASL mechanism is supported. This is required for example to connect to an Azure EventHub Kafka endpoint.

/kind enhancement
/area local-api

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 61.65%. Comparing base (d25633d) to head (9921780).
⚠️ Report is 40 commits behind head on master.

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #3872      +/-   ##
==========================================
+ Coverage   61.61%   61.65%   +0.04%     
==========================================
  Files         406      406              
  Lines       41850    41871      +21     
==========================================
+ Hits        25784    25816      +32     
+ Misses      13936    13929       -7     
+ Partials     2130     2126       -4     

Flag	Coverage Δ
bats	45.68% <0.00%> (+0.04%)	⬆️
unit-linux	34.67% <100.00%> (+0.04%)	⬆️
unit-windows	24.54% <100.00%> (+0.02%)	⬆️

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[acm-073]

Dear maintainer team,

I understand you're probably overloaded with PRs... but is there any chance this one gets merged in the near future? That would really be great!

Thanks for a short feedback
Albrecht

[Copilot]

Pull Request Overview

This PR implements SASL authentication support for Kafka acquisition to enable connections to endpoints like Azure EventHub. The implementation currently supports only the "PLAIN" SASL mechanism as requested in issue #3336.

Key changes:

• Added SASL configuration structure with mechanism, credentials, and SSL settings
• Implemented SASL mechanism creation with support for PLAIN authentication
• Enhanced Kafka dialer to handle SASL authentication and SSL connections

Reviewed Changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 2 comments.

File	Description
pkg/acquisition/modules/kafka/kafka.go	Added SASL configuration struct, SASL mechanism creation, and enhanced dialer with SASL support
pkg/acquisition/modules/kafka/kafka_test.go	Added test cases for valid PLAIN SASL configuration and unsupported SCRAM mechanism

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[acm-073]

@LaurenceJJones I have fixed the review findings from the automated Copilot review... could you maybe have another look? Thanks!