ADR for expose runner's machine info in log. (#354)

* ADR for expose runner's machine info in log.

* rename

* Update docs/adrs/0354-runner-machine-info.md

Co-Authored-By: Hugo van Kemenade <hugovk@users.noreply.github.com>

* Update docs/adrs/0354-runner-machine-info.md

Co-Authored-By: Hugo van Kemenade <hugovk@users.noreply.github.com>

* Update docs/adrs/0354-runner-machine-info.md

Co-Authored-By: Hugo van Kemenade <hugovk@users.noreply.github.com>

* Update 0354-runner-machine-info.md

Co-authored-by: Hugo van Kemenade <hugovk@users.noreply.github.com>

docs/adrs/0354-runner-machine-info.md

@@ -0,0 +1,35 @@
+# ADR 354: Expose runner machine info
+
+**Date**: 2020-03-02
+
+**Status**: Pending
+
+## Context
+
+- Provide a mechanism in the runner to include extra information in `Set up job` step's log.
+  Ex: Include OS/Software info from Hosted image.
+
+## Decision
+
+The runner will look for a file `.setup_info` under the runner's root directory, The file can be a JSON with a simple schema.
+```json
+[
+  {
+    "group": "OS Detail",
+    "detail": "........"
+  },
+  {
+    "group": "Software Detail",
+    "detail": "........"
+  }
+]
+```
+The runner will use `##[group]` and `##[endgroup]` to fold all detail info into an expandable group.
+
+Both [virtual-environments](https://github.com/actions/virtual-environments) and self-hosted runners can use this mechanism to add extra logging info to the `Set up job` step's log.
+
+## Consequences
+
+1. Change the runner to best effort read/parse `.extra_setup_info` file under runner root directory.
+2. [virtual-environments](https://github.com/actions/virtual-environments) generate the file during image generation.
+3. Change MMS provisioner to properly copy the file to runner root directory at runtime.