.github/workflows/repoman.yml: Use script to auto run the latest rm

By using a seperate script instead of running everything in the yml
file, we gain the ability to use and manipulate variables. This
means that we can now automatically run the latest version of
repoman, which should make this more hands-off by removing the
need to update this every now and then.

Signed-off-by: Andrew Ammerlaan <andrewammerlaan@riseup.net>

scripts/setup-and-run-repoman.sh

@@ -0,0 +1,30 @@
+#! /usr/bin/env bash
+# Maintainer: Andrew Ammerlaan <andrewammerlaan@riseup.net>
+#
+# This sets up repoman and runs the latest version
+#
+# TODO: Force repoman to output in colour
+
+### Setup prerequisites
+python3 -m pip install --upgrade pip
+pip install lxml pyyaml
+sudo groupadd -g 250 portage
+sudo useradd -g portage -d /var/tmp/portage -s /bin/false -u 250 portage
+
+### Sync the portage repository
+git clone https://github.com/gentoo/portage.git
+cd portage
+
+# Get all versions, and read into array
+mapfile -t RM_VERSIONS < <( git tag | grep repoman | sort -u )
+
+# Select latests version (last element in array)
+RM_VERS="${RM_VERSIONS[-1]}"
+
+# Checkout this version
+git checkout tags/${RM_VERS} -b ${RM_VERS}
+
+cd ..
+
+### Run repoman
+python3 portage/repoman/bin/repoman -dx full