Before this commit, the user had to manually set the job repository and transaction
manager on `JobBuilder` and `StepBuilder` instances with a chained call to
`.repository(jobRepository)` and `.transactionManager(transactionManager)`.
This is error prone and can lead to runtime errors if these properties are not set.
This commit introduces new APIs to guide the user to set these properties at
builder creation time.
Resolves#4192