[gnome-build-meta.wiki] Update OpenQA for GNOME developers

[Sam Thursfield <sthursfield src gnome org>]

commit 5f323e58927a2a28a5b6c9c81cfa33f8eb806c43
Author: Sam Thursfield <sam afuera me uk>
Date:   Fri Sep 24 16:26:45 2021 +0000

    Update OpenQA for GNOME developers

 openqa/OpenQA-for-GNOME-developers.md | 19 ++++++++++++++++++-
 1 file changed, 18 insertions(+), 1 deletion(-)
---
diff --git a/openqa/OpenQA-for-GNOME-developers.md b/openqa/OpenQA-for-GNOME-developers.md
index 8939d7a..b85594d 100644
--- a/openqa/OpenQA-for-GNOME-developers.md
+++ b/openqa/OpenQA-for-GNOME-developers.md
@@ -92,5 +92,22 @@ When adding or debugging tests you probably don't want to wait for a full Gitlab
 
 4. Run this command inside the gnome-build-meta clone to start the openqa_worker image:
 
-        podman run --privileged --rm -it -v ./openqa:/tests -v ./installer.iso:/installer.iso --entrypoint 
isotovideo quay.io/ssssam/openqa_worker  $(jq -jr 'keys[] as $k | "\($k)=\(.[$k]) "'  < vars.json) 
CASEDIR=/tests
+        podman run --privileged -it \
+            -v ./openqa:/tests -v ./installer.iso:/installer.iso \
+            --entrypoint isotovideo quay.io/ssssam/openqa_worker  \
+            $(jq -jr 'keys[] as $k | "\($k)=\(.[$k]) "'  < vars.json) \
+            CASEDIR=/tests
 
+    The test log will be written to stdout, the other data is still inside the container.
+
+5. Find the ID of the container you just ran, using `podman ps -a -l`  
+
+6. Copy the test results and video out of the container:
+
+        podman cp 12345678abc:/testresults ./testresults 
+        podman cp 12345678abc:/video.ogv .
+        # See all files in the container by running: podman export 12345678abc | tar -v -t | less
+
+7. Remove the container with `podman rm` when you are done.
+
+It's common to use `save_screenshot` when writing testcases, which gives you a `.png` which you can then 
convert into a Needle.