Update src/map_viz.py

Adding title for map viz

src/map_viz.py

@@ -80,4 +80,5 @@ def calling_map_viz(counts_df):
     ax.add_artist(collection)
     ax.set_xlim([100, 1900])
     ax.set_ylim([1800, 0])
+    ax.set_title(last_date + " " + last_time)
     return fig