feat(#3957): fix the description of xcop a bit

Author: volodya-lombrozo

README.md

@@ -315,8 +315,9 @@ before sending us your pull request please run full Maven build:
 mvn clean install -Pqulice
 ```
 
-You will need [Maven 3.3+](https://maven.apache.org), Java 11+ and
-[xcop](https://github.com/yegor256/xcop) 0.8.0+ installed.
+You will need [Maven 3.3+](https://maven.apache.org) and Java 11+ installed.
+Also, if you have [xcop](https://github.com/yegor256/xcop) installed, make sure 
+it is version `0.8.0`+.
 
 ## Special thanks