[FAB-5618] Allow directory to contain spaces

Added quotes to $CURRENT_DIR in byfn.sh so that the current directory
can contain spaces and the script will still run properly.

Change-Id: I3853e3398c29c55c46603477fada5db023808431
Issue-id: FAB-5618
Signed-off-by: Ethan Coeytaux <eacoeytaux@gmail.com>

first-network/byfn.sh

@@ -161,11 +161,11 @@ function replacePrivateKey () {
  CURRENT_DIR=$PWD
  cd crypto-config/peerOrganizations/org1.example.com/ca/
  PRIV_KEY=$(ls *_sk)
- cd $CURRENT_DIR
+ cd "$CURRENT_DIR"
  sed $OPTS "s/CA1_PRIVATE_KEY/${PRIV_KEY}/g" docker-compose-e2e.yaml
  cd crypto-config/peerOrganizations/org2.example.com/ca/
  PRIV_KEY=$(ls *_sk)
- cd $CURRENT_DIR
+ cd "$CURRENT_DIR"
  sed $OPTS "s/CA2_PRIVATE_KEY/${PRIV_KEY}/g" docker-compose-e2e.yaml
  # If MacOSX, remove the temporary backup of the docker-compose file
  if [ "$ARCH" == "Darwin" ]; then