chore(deps): update ghcr.io/marketsquare/robotframework-browser/rfbrowser-stable docker tag to v19.12.0

Author: renovate[bot]

test-module.sh

@@ -8,7 +8,7 @@ ssh_key="$(cat $SSH_KEYFILE)"
 
 podman run -i \
     -v .:/home/pwuser/ns8-module:z \
-    --name rf-core-runner ghcr.io/marketsquare/robotframework-browser/rfbrowser-stable:19.1.2 \
+    --name rf-core-runner ghcr.io/marketsquare/robotframework-browser/rfbrowser-stable:19.12.0 \
     bash -l -s <<EOF
     set -e
     echo "$ssh_key" > /home/pwuser/ns8-key