README: fix broken image

Author: kbdharun

README.md

@@ -5,7 +5,7 @@
 
 Python command-line client for [tldr pages](https://github.com/tldr-pages/tldr).
 
-![tldr pages example](https://raw.github.com/tldr-pages/tldr/main/images/tldr.svg)
+![tldr pages example](https://raw.github.com/tldr-pages/tldr/main/images/tldr-dark.png)
 
 ## Installation