Bump mongo-java-driver from 3.12.5 to 3.12.6 in /core (testcontainers…

…#3024)

Bumps [mongo-java-driver](https://github.com/mongodb/mongo-java-driver) from 3.12.5 to 3.12.6.
- [Release notes](https://github.com/mongodb/mongo-java-driver/releases)
- [Commits](mongodb/mongo-java-driver@r3.12.5...r3.12.6)

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Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

core/build.gradle

@@ -202,7 +202,7 @@ dependencies {
     testCompile 'org.apache.httpcomponents:httpclient:4.5.9'
     testCompile 'redis.clients:jedis:3.3.0'
     testCompile 'com.rabbitmq:amqp-client:5.9.0'
-    testCompile 'org.mongodb:mongo-java-driver:3.12.5'
+    testCompile 'org.mongodb:mongo-java-driver:3.12.6'
 
     testCompile ('org.mockito:mockito-core:3.4.6') {
         exclude(module: 'hamcrest-core')