replace keys.gnupg.net with curl from rvm.io (#16568)

Vagrantfile

@@ -45,16 +45,8 @@ sudo apt-get install \
 # Install rvm
 read RUBY_VERSION < .ruby-version
 
-gpg_command="gpg --keyserver hkp://keys.gnupg.net --recv-keys 409B6B1796C275462A1703113804BB82D39DC0E3 7D2BAF1CF37B13E2069D6956105BD0E739499BDB"
-$($gpg_command)
-if [ $? -ne 0 ];then
-  echo "GPG command failed, This prevented RVM from installing."
-  echo "Retrying once..." && $($gpg_command)
-  if [ $? -ne 0 ];then
-    echo "GPG failed for the second time, please ensure network connectivity."
-    echo "Exiting..." && exit 1
-  fi
-fi
+curl -sSL https://rvm.io/mpapis.asc | gpg --import
+curl -sSL https://rvm.io/pkuczynski.asc | gpg --import
 
 curl -sSL https://raw.githubusercontent.com/rvm/rvm/stable/binscripts/rvm-installer | bash -s stable --ruby=$RUBY_VERSION
 source /home/vagrant/.rvm/scripts/rvm