feat: Update version from 2.5.0 to 2.6.0

[Joel-hanson]

This pull request updates the project version from 2.5.0 to 2.6.0 across the codebase and documentation to reflect the new release. The main changes are version bumps in configuration files and source code.

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 I was expecting the README to be updated in this PR to remove the warning about Kafka version support. Am I missing something?

[Joel-hanson]

Missed to remove that, Will raise a new PR @dalelane