Use 3.11.6 for EmbeddedCassandra with enforced Guava 18

Use Cassandra 3.11. Force Guava18

With DSE switched to Guava 31 we had test failures
caused by Guava 31 on the path
which caused EmbeddedCassandra failures (Access, DIGIT)
as Cassandra 3.0 and 3.11 are not ready for new Guava.

This change:
* forces Cassandra 3.11 for the EmbeddedCassandra test
* forces Guava 18 for "dse" flavor (same as "oss" already did).

Author: tlasica

scala/maven/dse/pom.xml

@@ -14,7 +14,7 @@
     <scala.main.version>2.11</scala.main.version>
     <scalatest.version>3.0.0</scalatest.version>
     <connector.version>2.0.10</connector.version>
-    <cassandra.version>3.2</cassandra.version>
+    <cassandra.version>3.11.10</cassandra.version>
     <junit.version>4.12</junit.version>
   </properties>
 
@@ -62,6 +62,13 @@
       <version>${cassandra.version}</version>
       <scope>test</scope>
     </dependency>
+    <!-- Force Guava 18 on Test CP, Required for Cassandra -->
+    <dependency>
+      <groupId>com.google.guava</groupId>
+      <artifactId>guava</artifactId>
+      <version>18.0</version>
+      <scope>test</scope>
+    </dependency>
   </dependencies>
 
   <repositories>
@@ -130,6 +137,9 @@
           <reportsDirectory>${project.build.directory}/surefire-reports</reportsDirectory>
           <junitxml>.</junitxml>
           <filereports>WDF TestSuite.txt</filereports>
+          <systemProperties>
+            <test.cassandra.version>${cassandra.version}</test.cassandra.version>
+          </systemProperties>
         </configuration>
         <executions>
           <execution>

scala/maven/oss/pom.xml

@@ -14,7 +14,7 @@
     <spark.version>2.2.2</spark.version>
     <scalatest.version>3.0.0</scalatest.version>
     <connector.version>2.0.10</connector.version>
-    <cassandra.version>3.2</cassandra.version>
+    <cassandra.version>3.11.10</cassandra.version>
     <junit.version>4.12</junit.version>
   </properties>
 
@@ -171,6 +171,9 @@
           <reportsDirectory>${project.build.directory}/surefire-reports</reportsDirectory>
           <junitxml>.</junitxml>
           <filereports>WDF TestSuite.txt</filereports>
+          <systemProperties>
+            <test.cassandra.version>${cassandra.version}</test.cassandra.version>
+          </systemProperties>
         </configuration>
         <executions>
           <execution>