Delete Old Files that no longer exist in the "website" folder of the main Branch. These files are out-of-date/un-maintained and include Google Analytics. (#491)

The following files moved to a new location
    - developers/buildingmahout.html
    - developers/developer-resources.html
    - developers/github.html
    - developers/githubPRs.html
    - developers/gsoc.html
    - developers/how-to-become-a-committer.html
    - developers/how-to-contribute.html
    - developers/how-to-release.html
    - developers/how-to-update-the-website.html
    - developers/issue-tracker.html
    - developers/patch-check-list.html
    - developers/thirdparty-dependencies.html
    - developers/version-control.html
    - general/downloads.html
    - general/mailing-lists.html
    - general/who-we-are.html

I believe the "minutes/2024/04/02/Meeting-Minutes.html" is a duplicate of "minutes/2024/04/03/Meeting-Minutes.html"

I can't find any equivalent file in the "main" branch for "minutes/2024/04/02/Meeting-Minutes.html" - you may want to recover this file and re-engineer a ".md" file to add to the main branch.

Co-authored-by: Niall Pemberton <niallp@apache.org>

Author: niallkp