add the support of multi coverage file for the baseline command + raises an error when the custom coverage can be increased

Author: anne-gaelle123inkt

README.md

@@ -108,7 +108,7 @@ The third required argument and `--report` has been removed, and should be repla
 `--reportGitlab=<file>`, `--reportCheckstyle=<file>` or `--reportText=<file>` 
 
 # Migrating from 2 to 3
-The baseline now also support multiple coverage files, as the inspect command.
+The baseline now also supports multiple coverage files, as the inspect command.
 An error is also raised if the baseline custom entry doesn't match the coverage.
 
 ## About us