docs: create publish_multiple_os_images_scripted_inputs runbook (#259)

PR with documentation for publishing multiple different os images for
scripted inputs tests purpose.

---------

Co-authored-by: Artem Rys <rysartem@gmail.com>

Author: mkolasinski-splunk

runbooks/publish_multiple_os_images_scripted_inputs.md

@@ -0,0 +1,12 @@
+# Runbook to publish multiple images of different Linux flavors and versions for scripted inputs tests
+
+Once there is new Splunk release, and [matrix](https://github.com/splunk/addonfactory-test-matrix-action) is updated, we need to make sure that Splunk images for scripted inputs tests are created and published.
+## Steps
+
+### Update OS images
+- check what OS are listed in definition of matrix in scripted inputs tests [here](https://github.com/splunk/addonfactory-workflow-addon-release/blob/v4.16/.github/workflows/reusable-build-test-release.yml#L1966)
+- if any is missing in [ta-automation-docker-images](https://cd.splunkdev.com/taautomation/ta-automation-docker-images/-/tree/main/dockerfiles) then add new Dockerfile
+
+### Create images and publish them to ECR
+- figure out what version of Splunk is needed (sha) using go/fetcher
+- trigger [pipeline](https://cd.splunkdev.com/taautomation/ta-automation-docker-images/-/pipelines/new) for every OS flavor separately