Remove iBicha from C# technical committee

[iBicha]

I've been added to the C# technical committee a few years ago, but unfortunately I wasn't able to contribute in any significant way to this project right after.
I figured I should remove myself to avoid misleading anyone contributing and waiting on a review etc.
Cheers

PR checklist

• Read the contribution guidelines.
• Run the following to build the project and update samples:

  ./mvnw clean package || exit
  ./bin/generate-samples.sh ./bin/configs/*.yaml || exit
  ./bin/utils/export_docs_generators.sh || exit
  

  (For Windows users, please run the script in WSL)
  Commit all changed files.
  This is important, as CI jobs will verify all generator outputs of your HEAD commit as it would merge with master.
  These must match the expectations made by your contribution.
  You may regenerate an individual generator by passing the relevant config(s) as an argument to the script, for example ./bin/generate-samples.sh bin/configs/java*.
  IMPORTANT: Do NOT purge/delete any folders/files (e.g. tests) when regenerating the samples as manually written tests may be removed.
• If your PR is targeting a particular programming language, @mention the technical committee members, so they are more likely to review the pull request.

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Summary by cubic

Remove @iBicha from the C# technical committee list in README to reflect current membership and avoid confusion about review availability.

^{Written for commit 46c338f. Summary will update on new commits.}

[cubic-dev-ai]

No issues found across 1 file

_{Re-trigger cubic}

[wing328]

thanks for helping us to move this project forward. all the best to your future endeavor