Add the Region env variable in the build command for setups that do not set it up

Author: Lambros Petrou

aws-codeguruprofiler-profilinggroup/README.md

@@ -14,7 +14,7 @@ automatically overwritten.
 After modifying the JSON schema or changing the handlers implementation make sure you do the following before sending a pull-request:
 
 ```
-pre-commit run --all-files && mvn clean package
+pre-commit run --all-files && AWS_REGION=us-east-1 mvn clean package
 ```
 
 **References**