allow (build and deploy) scripts to run on a mac, not just linux

this is annoying for local builds:
```
if [[ $OSTYPE != "linux-gnu" ]]; then
    echo -e "\e[91mERROR: This script has only been tested on Linux. Currently, only Linux (debian) is supported. Please run in Cloud Shell or in a VM running Linux".
    exit;
fi
```

i think its related to how we used to use `sed` which is BSD flags on a mac.