Prevent `Neo4jContainer#withEnterpriseEdition` from overwriting version

[fbiville]

It would be nice if one could be able to write something like:

new Neo4jContainer<>(DockerImageName.parse("neo4j").withTag("4.2"))
     .withEnterpriseEdition()

instead of the current alternative:

new Neo4jContainer<>(DockerImageName.parse("neo4j").withTag("4.2-enterprise"))
     .withEnv("NEO4J_ACCEPT_LICENSE_AGREEMENT", "yes")

I cannot currently use withEnterpriseEdition as it overwrites the image name and version with the default ones.

I find the first snippet a bit easier to write and read.
Also, withEnterpriseEdition does the extra LicenseAcceptance.assertLicenseAccepted check which is not easily replicated otherwise.

[eddumelendez]

This is already implemented.