[circle-mlir/infra] Discard output from the cd command

This commit fixes the issue when `cd` is followed by the `pwd` in a
bash one-liner for getting the location of the script. The `cd` command
can print the destination directory in case when one has the CDPATH
environmental variable set which breaks the one-liner functionality.

ONE-DCO-1.0-Signed-off-by: Arkadiusz Bokowy <a.bokowy@samsung.com>

Author: arkq

circle-mlir/infra/overlay/prepare-venv

@@ -34,7 +34,7 @@ fi
 
 set -e
 
-DRIVER_PATH="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
+DRIVER_PATH="$(cd "$(dirname "${BASH_SOURCE[0]}")" >/dev/null && pwd)"
 if [[ -z "$VENV_NAME" ]]; then
   VENV_NAME="venv"
 fi