update README.md (#468)

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Author: pdibenedetto

README.md

@@ -218,7 +218,7 @@ Run all **unit** tests (Maven Surefire Plugin): `./mvnw test`
 Run all **integration & web** tests (Maven Failsafe plugin):
 
 1. Make sure no conflicting Docker containers are currently running: `docker ps`
-2. Make sure the test classes have been compiled and the frontend has been build and is part of the `target/classes/public` folder: `./mvnw package -DskipTest`
+2. Make sure the test classes have been compiled and the frontend has been built and is part of the `target/classes/public` folder: `./mvnw package -DskipTest`
 3. Execute `./mvnw failsafe:integration-test failsafe:verify`
 
 Run **all tests** together: