Testcontainers migration

[BillyYccc]

Migrate our embedded databases for testing to Testcontainers discussed in https://github.com/eclipse-vertx/vertx-sql-client/pull/381#issuecomment-515672725. (Actually we have given a try a long time before)

Pros:

• Single dependency on the Testcontainers
• Better support for the new features and new versions
• the same way of using it in testing with different databases
• Easier for extensibility to other databases

Cons:

• Looks like we can not test the Unix socket feature in the Mac OS X(see https://github.com/docker/for-mac/issues/483), but I think it will be fine since that part of code will not change too much.

[benbenw]

I have a patch for the Postresql tests (excluding the Unis socket test)

Waiting for the merge of #412 before submitting.