chore(deps): update dependency org.apache.maven.plugins:maven-failsafe-plugin to v3.0.0-m4 (#7)

Author: renovate-bot

pom.xml

@@ -296,7 +296,7 @@
       <plugin>
         <groupId>org.apache.maven.plugins</groupId>
         <artifactId>maven-failsafe-plugin</artifactId>
-        <version>3.0.0-M3</version>
+        <version>3.0.0-M4</version>
         <configuration>
           <systemPropertyVariables>
             <spanner.testenv.config.class>com.google.cloud.spanner.GceTestEnvConfig</spanner.testenv.config.class>