* Make exec test assert Envoy version - it was not rebuilding before and so often ran against wrong version. This makes 1.10 fail consistenty.
* Switch Envoy exec to use a named pipe rather than FD magic since Envoy 1.10 doesn't support that.
* Refactor to use an internal shim command for piping the bootstrap through.
* Fmt. So sad that vscode golang fails so often these days.
* go mod tidy
* revert go mod tidy changes
* Revert "ignore consul-exec tests until fixed (#5986)"
This reverts commit 683262a6869033cb79e68fa1dba0f9ea83e9187d.
* Review cleanups
* Default gRPC port; Start on some basic tests for argument and ENV handling; Make Exec test less platform-dependent.
* Allow hot-restarts
* Remove debug
Play a trick with CLOEXEC to pass the envoy bootstrap configuration as
an open file descriptor to the exec'd envoy process. The file only
briefly touches disk before being unlinked.
We convince envoy to read from this open file descriptor by using the
/dev/fd/$FDNUMBER mechanism to read the open file descriptor as a file.
Because the filename no longer has an extension envoy's sniffing logic
falls back on JSON instead of YAML, so the bootstrap configuration must
be generated as JSON instead.
