Fix bindingTestScript.sh shebang and use /usr/bin/env to find bash

[sepeth]

This change allows people to run this script on macOS, which has quite an old version of bash at /bin/bash. Without it, I see the following error:

build/bindingtester/localClusterStart.sh: line 209: syntax error near unexpected token `>'
build/bindingtester/localClusterStart.sh: line 209: `  elif "${BINDIR}/fdbcli" -C "${FDBCONF}" --exec "kill; kill ${FDBCLUSTERTEXT}; sleep 3" --timeout 120 &>> "${LOGDIR}/fdbcli-kill.log"'

Also, note that the old shebang in bindingTestScript.sh was also missing the ! character.

localClusterStart.sh didn't need to be changed since it is directly sourced by bindingTestScript.sh, but there's no harm to correct it, and it could perhaps become useful if one tries to use it directly.

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[xis19]

Thanks for fixing this issue!

Meanwhile we have bindingtest2 which is implemented in Python3 and might be less error prone.