Remove Modin from Ray wheels. (#5647)

There are several reasons for this:

* We no longer support python2
* There should be only 1 way of installing Modin
  * Issue management on these wheels
* I have never heard of anyone using this feature
* It is rarely kept up to date
* Modin depends on specific versions of Ray because of past API changes

thirdparty/scripts/build_modin.sh

@@ -1,29 +0,0 @@
-#!/bin/bash
-
-set -x
-
-# Cause the script to exit if a single command fails.
-set -e
-
-if [[ -z  "$1" ]]; then
-  PYTHON_EXECUTABLE=`which python`
-else
-  PYTHON_EXECUTABLE=$1
-fi
-
-PYTHON_VERSION="$($PYTHON_EXECUTABLE -c 'import sys; print(sys.version_info[0])')"
-
-TP_DIR=$(cd "$(dirname "${BASH_SOURCE:-$0}")"; pwd)/../
-MODIN_VERSION=0.5.0
-MODIN_WHEELS_FNAME="modin-$MODIN_VERSION-py$PYTHON_VERSION-none-any.whl"
-MODIN_WHEELS_URL="https://github.com/modin-project/modin/releases/download/v$MODIN_VERSION/"
-
-pushd $TP_DIR/../python/ray/
-rm -rf modin
-mkdir modin
-pushd modin
-curl -kL --silent "$MODIN_WHEELS_URL$MODIN_WHEELS_FNAME" -o "$MODIN_WHEELS_FNAME"
-unzip -qq "$MODIN_WHEELS_FNAME"
-rm "$MODIN_WHEELS_FNAME"
-popd
-popd

thirdparty/scripts/setup.sh

@@ -26,8 +26,3 @@ echo "Python library will be built."
 fi
 
 unamestr="$(uname)"
-
-##############################################
-# modin
-##############################################
-bash "$TP_SCRIPT_DIR/build_modin.sh" $PYTHON_EXECUTABLE