[module:vault] secrets should be a list/seq rather than option

[pPanda-beta]

It's a pretty common use case that someone would require more than one secrets, so I would suggest to use a map (same as java field) or at least a Seq[VaultContainer.Secrets] (a better name would be VaultContainer.Secret) instead of Option.

testcontainers-scala/modules/vault/src/main/scala/com/dimafeng/testcontainers/VaultContainer.scala

Line 9 in c2331d7

secrets: Option[VaultContainer.Secrets] = None) extends SingleContainer[JavaVaultContainer[?]] {