Remove fallback to current year in footer

The footer template now only uses config.extra.current_year for the year value, removing the fallback to the current year via now().year.

Author: roshit-omanakuttan

docs/overrides/partials/footer.html

@@ -1,4 +1,4 @@
-{% set year = (config.extra.current_year or None) or now().year %}
+{% set year = (config.extra.current_year or None)  %}
 <div class="wl-footer">
   © {{ year }} Wow Labz · Built with <a href="https://squidfunk.github.io/mkdocs-material/" target="_blank" rel="noopener">MkDocs Material</a>.
 </div>