Update applications.rst

Author: Evolutionary-Intelligence

docs/sphinx/source/applications.rst

@@ -102,7 +102,7 @@ Open-Source Cases
 Till now, this Python library `PyPop7` has been required and/or introduced
 (at least) in the following **open-source** projects on **GitHub**:
 
-* **18**：https://github.com/GMC-DRL/Awesome-MetaBBO
+* **18**: https://github.com/GMC-DRL/Awesome-MetaBBO
 
   * "Many outstanding teams have developed excellent GitHub repositories
     for the Evolutionary Computation community, and we are pleased to