Many of our scripts have a non-portable interpreter line for bash and
use bash-specific variables like `BASH_SOURCE`. Update the interpreter
line to be portable between various Linuxes and macOS without
complaint from posix shell users.
Use HCP Consul and HCP Vault for the Consul and Vault clusters used in E2E testing. This has the following benefits:
* Without the need to support mTLS bootstrapping for Consul and Vault, we can simplify the mTLS configuration by leaning on Terraform instead of janky bash shell scripting.
* Vault bootstrapping is no longer required, so we can eliminate even more janky shell scripting
* Our E2E exercises HCP, which is important to us as an organization
* With the reduction in configurability, we can simplify the Terraform configuration and drop the complicated `provision.sh`/`provision.ps1` scripts we were using previously. We can template Nomad configuration files and upload them with the `file` provisioner.
* Packer builds for Linux and Windows become much simpler.
tl;dr way less janky shell scripting!
Provisions vault with the policies described in the Nomad Vault integration
guide, and drops a configuration file for Nomad vault server configuration
with its token. The vault root token is exposed to the E2E runner so that
tests can write additional policies to vault.
Tim Gross