add plot example to readme [skip-ci]

README.md

@@ -784,9 +784,11 @@ In addition, both plot types share two innermost GC content and GC skew rings. T
 Custom plot labels (text in the center) can be provided via `--label`:
 
 ```bash
-bakta_plot --sequences 2 --label="line 1|line 2|line 3" input.json
+--sequences 2 --dpi 150 --size 4 --prefix plot-cog-p2 --type cog --label="pO157|plasmid, 92.7 kbp"
 ```
 
+![Plot example of Bakta test genome.](/examples/plot-cog-p2.png)
+
 ## Auxiliary scripts
 
 Often, the usage of Bakta is a necessary upfront task followed by deeper analyses implemented in custom scripts. In [scripts](scripts) we'd like to collect & offer a pool of scripts addressing common tasks: