Add index.html copy for zyra-poster.html

Copy zyra-poster.html to index.html in the build directory.

Signed-off-by: Eric Hackathorn <62408375+Hackshaven@users.noreply.github.com>

Author: Hackshaven

.github/workflows/docs-pages.yaml

@@ -45,6 +45,7 @@ jobs:
           python poster/scripts/build_poster.py
           mkdir -p docs/build/poster
           cp poster/html/zyra-poster.html docs/build/poster/
+          cp poster/html/zyra-poster.html docs/build/poster/index.html
           cp poster/html/zyra-poster-print.html docs/build/poster/
           cp poster/html/hrrr_wind_interactive.html docs/build/poster/
           cp poster/html/hrrr_temp_interactive.html docs/build/poster/