update thumbnail link

Author: HammadTheOne

doc/python/bio-alignment-chart.md

@@ -29,7 +29,7 @@ jupyter:
     order: 1
     page_type: u-guide
     permalink: python/alignment-chart/
-    thumbnail: thumbnail/alignment-chart.png
+    thumbnail: thumbnail/alignment_chart.png
 ---
 
 ## Alignment Viewer (link to dash alignment section below)

doc/python/bio-volcano-plot.md

@@ -30,15 +30,15 @@ jupyter:
     order: 1
     page_type: u-guide
     permalink: python/volcano-plot/
-    thumbnail: thumbnail/volcano-plot.png
+    thumbnail: thumbnail/volcano_plot.png
 ---
 
 ## VolcanoPlot
 Volcano Plot interactively identifies clinically meaningful markers in genomic experiments, i.e., markers that are statistically significant and have an effect size greater than some threshold. Specifically, volcano plots depict the negative log-base-10 p-values plotted against their effect size.
 
 ```python
 import pandas as pd
-import dash_bio 
+import dash_bio
 
 
 df = pd.read_csv(