Revert "Add a gnet utility"

This reverts commit 3c1902fc.

This was accidentally re-added from an old version of the branch before
!265 was merged. It should not have been re-added.
9 jobs for 265-really-drop-gnet in 17 minutes (queued for 2 seconds)
Status Job ID Name Coverage
  Build
passed #92312
cross-android_api21_arm64

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cross-android_api28_arm64

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cross-mingw64

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fedora-autotools-x86_64

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fedora-x86_64

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freebsd-11 allowed to fail manual
freebsd-11-x86_64
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win32
msys2-mingw32

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win32
vs2017-x64

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  Coverage
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coverage

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73.4%