Add --exit to runOracle script

[felipecrs]

This would allow me to create a pre-started Oracle container so I could take advantage of faster start times, such as:

FROM my-oracle:ee-19.3.0

ENV ORACLE_PWD=sys

RUN exec $ORACLE_BASE/$RUN_FILE --exit

Then:

$ docker build -t my-pre-started-oracle .
$ docker push my-pre-started-oracle
$ docker run -p [...] my-pre-started-oracle

This would come very in handy for my CI environment, as it drops the start time from 45 minutes to less than 3.

[yunus-qureshi]

Already implemented as part of

#2188