Guava 32.1.2: terminally deprecated method in sun.misc.Unsafe has been called

When using the jib maven plugin 3.5.2, there's a (strong) warning about usage of a "terminally deprecated method".

```
164119 [INFO] --- jib:3.5.2:build (default-cli) @ app ---
164402 [WARNING] 'mainClass' configured in 'maven-jar-plugin' is not a valid Java class: ${start-class}
164450 [INFO] Running extension: com.google.cloud.tools.jib.maven.extension.springboot.JibSpringBootExtension
164450 [INFO] Running Jib Spring Boot extension
164453 [INFO]
164453 [INFO] Containerizing application to xxx...
164455 [WARNING] Base image 'xxx' does not use a specific image digest - build may not be reproducible
WARNING: A terminally deprecated method in sun.misc.Unsafe has been called
WARNING: sun.misc.Unsafe::objectFieldOffset has been called by com.google.common.util.concurrent.AbstractFuture$UnsafeAtomicHelper (file:/builds/bol/partner_iam/code/teamadvertisingaccountmanagement/services/sam/.m2/repository/com/google/guava/guava/32.1.2-jre/guava-32.1.2-jre.jar)
WARNING: Please consider reporting this to the maintainers of class com.google.common.util.concurrent.AbstractFuture$UnsafeAtomicHelper
WARNING: sun.misc.Unsafe::objectFieldOffset will be removed in a future release
```

In order to avoid future breakage, it would be great if the Guava dependency could be updated to a newer version.

Start by locating the Jib Maven plugin's Guava dependency declaration and inspect how the 3.5.2 build invokes it. Reproduce the Maven containerization build, then verify that a compatible newer Guava version removes the terminal deprecation warning without breaking the plugin.

Written by the indexing model from the issue text.