Add installation instructions how to install kn-plugin-event via Homebrew

[creydr]

Changes

• :gift: Installation instructions for Homebrew

[knative-prow[bot]]

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This pull-request has been approved by: creydr Once this PR has been reviewed and has the lgtm label, please assign evankanderson for approval. For more information see the Kubernetes Code Review Process.

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[codecov[bot]]

Codecov Report

Merging #279 (a344854) into main (6cb55e5) will not change coverage. The diff coverage is n/a.

@@           Coverage Diff           @@
##             main     #279   +/-   ##
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  Coverage   68.17%   68.17%           
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  Files          35       35           
  Lines        1128     1128           
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  Hits          769      769           
  Misses        299      299           
  Partials       60       60           

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[dsimansk]

@creydr gentle ping. Fancy going back to this PR? :)

[github-actions[bot]]

This Pull Request is stale because it has been open for 90 days with no activity. It will automatically close after 30 more days of inactivity. Reopen with /reopen. Mark as fresh by adding the comment /remove-lifecycle stale.