Fix typo in README

@Gharaee
Could you review this cleanup?

**Changes:**
- Fixed typo: 'densly' → 'densely'

README.md

@@ -131,7 +131,7 @@ It organizes species into groups based on shared characteristics and genetic rel
 
   
 ### IV. RGB image
-Original insect images from 16 most densly populated orders of the BIOSCAN-1M Insect dataset. 
+Original insect images from 16 most densely populated orders of the BIOSCAN-1M Insect dataset. 
 The numbers below each image identify the number of images in each class, and clearly illustrate the degree of class imbalance in the BIOSCAN-1M Insect dataset.
 
 <div align="center">