Amend container shutdown to catch and log for all Exception classes

[rnorth]

Replacement for #1420 to fix incomplete error handling
Refs #1379

We found that unfortunately #1420 had some issues:

• It would rethrow an exception in some cases, making tests fail unnecessarily
• the code which parsed ConflictException messages didn't actually correctly detect the error message in the exception.
• in addition, the exception types being caught were actually thrown off by the use of a Proxy

We decided to simplify and just catch Exception, since we don't actually care about what might have caused container deletion to fail.

It is causing exceptions like these, failing tests:

Gradle Test Executor 1 > org.testcontainers.junit.GenericContainerRuleTest > sharedMemorySetTest FAILED
    java.lang.reflect.UndeclaredThrowableException
        at com.sun.proxy.$Proxy35.exec(Unknown Source)
        at org.testcontainers.utility.ResourceReaper.stopContainer(ResourceReaper.java:233)
        at org.testcontainers.utility.ResourceReaper.stopAndRemoveContainer(ResourceReaper.java:212)
        at org.testcontainers.containers.GenericContainer.stop(GenericContainer.java:396)
        at org.testcontainers.lifecycle.Startable.close(Startable.java:18)
        at org.testcontainers.junit.GenericContainerRuleTest.sharedMemorySetTest(GenericContainerRuleTest.java:413)
        Caused by:
        java.lang.reflect.InvocationTargetException
            at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
            at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
            at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
            at java.lang.reflect.Method.invoke(Method.java:498)
            at org.testcontainers.dockerclient.AuditLoggingDockerClient.lambda$wrappedCommand$14(AuditLoggingDockerClient.java:98)
            ... 6 more
            Caused by:
            com.github.dockerjava.api.exception.ConflictException: {"message":"Cannot kill container: 6f87edb101f9d5534a872e0c3182c789ef0d8d029f1f42311c4ece540db3a2ff: Container 6f87edb101f9d5534a872e0c3182c789ef0d8d029f1f42311c4ece540db3a2ff is not running"}
                at org.testcontainers.dockerclient.transport.okhttp.OkHttpInvocationBuilder.execute(OkHttpInvocationBuilder.java:274)
                at org.testcontainers.dockerclient.transport.okhttp.OkHttpInvocationBuilder.execute(OkHttpInvocationBuilder.java:254)
                at org.testcontainers.dockerclient.transport.okhttp.OkHttpInvocationBuilder.post(OkHttpInvocationBuilder.java:115)
                at com.github.dockerjava.core.exec.KillContainerCmdExec.execute(KillContainerCmdExec.java:30)
                at com.github.dockerjava.core.exec.KillContainerCmdExec.execute(KillContainerCmdExec.java:11)
                at com.github.dockerjava.core.exec.AbstrSyncDockerCmdExec.exec(AbstrSyncDockerCmdExec.java:21)
                at com.github.dockerjava.core.command.AbstrDockerCmd.exec(AbstrDockerCmd.java:35)
                at com.github.dockerjava.core.command.KillContainerCmdImpl.exec(KillContainerCmdImpl.java:50)
                ... 11 more

[rnorth]

@bsideup I've just tweaked the exception logging a little - I realised that if we're logging an exception message, then it makes far more sense to log the root cause exception's message.