update to remove -a option from kubectl get pod and kubectl get pods.

[rddill-IBM]

The -a option on kubectl get pod and kubectl get pods has been deprecated. Running it with the current version of kubectl on IBM Cloud results in this error message:

Flag --show-all has been deprecated, will be removed in an upcoming release

This pull request updates the following scripts by removing the -a option

cs-offerings/scripts/create/chaincode_install.sh
cs-offerings/scripts/create/chaincode_instantiate.sh
cs-offerings/scripts/create/create_blockchain.sh
cs-offerings/scripts/create/create_channel.sh
cs-offerings/scripts/create/create_composer-playground.sh
cs-offerings/scripts/create/join_channel.sh
cs-offerings/scripts/delete/delete_blockchain.sh
cs-offerings/scripts/delete/delete_chaincode-install.sh
cs-offerings/scripts/delete/delete_chaincode-instantiate.sh
cs-offerings/scripts/delete/delete_channel-pods.sh
cs-offerings/scripts/wipe_shared.sh

[mrshah-at-ibm]

Thanks @rddill-IBM