fix: remove kafka 4 incompatible message from readme

[Joel-hanson]

This pull request makes a minor documentation update by removing an outdated statement about Kafka version support from the README.md.

Type of change

Please delete options that are not relevant.

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• This change requires a documentation update

How Has This Been Tested?

Checklist

• My code follows the style guidelines of this project
• I have performed a self-review of my code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• My changes generate no new warnings
• I have added tests that prove my fix is effective or that my feature works
• New and existing unit tests pass locally with my changes
• Any dependent changes have been merged and published in downstream modules

[thajinushehin]

LGTM

[dalelane]

@Joel-hanson @thajinushehin FYI - this would have been better tagged as a "docs" commit. "fix" is used to identify a bug fix, but no bugs were fixed here.

Typical conventional commit types are:

• feat: Introduces a new feature.
• fix: Patches a bug.
• docs: Documentation-only changes.
• style: Changes that do not affect the meaning of the code (white-space, formatting, etc).
• refactor: A code change that neither fixes a bug nor adds a feature.
• perf: Improves performance.
• test: Adds missing tests or corrects existing tests.
• chore: Changes to the build process or auxiliary tools and libraries such as documentation generation.