[test] re-enable integration tests

Downgrade maven-surefire-plugin to 3.5.2 to run all integration tests again and
also see failures.

Author: line-o

exist-parent/pom.xml

@@ -807,7 +807,8 @@
                 <plugin>
                     <groupId>org.apache.maven.plugins</groupId>
                     <artifactId>maven-surefire-plugin</artifactId>
-                    <version>3.5.3</version>
+                    <!-- NOTE: version 3.5.3 fails to run XSuite tests -->
+                    <version>3.5.2</version>
                     <dependencies>
                         <dependency>
                             <groupId>org.junit.platform</groupId>