pgAgent commit: Fixed an issue - when two jobs starts at the same time,

Fixed an issue - when two jobs starts at the same time, and sometime -
it ends up creating the same name as random string used as temporary
directory, and because - they were fetched at the same time, the
implemnetation does not find that directory exists.

In order to solve the issue - we will be using the job_id and step_id
as the prefix along with the random string while generating the
temporaty directory name. That will guarantee that the directory does
not exist at that time.

Reviewed: Neel Patel <neel(dot)patel(at)enterprisedb(dot)com>

Branch
------
master

Details
-------
https://git.postgresql.org/gitweb?p=pgagent.git;a=commitdiff;h=d4abe962a3131e48dd7f43542c5a91331b4aa92f
Author: Dave Page <dpage(at)pgadmin(dot)org>

Modified Files
--------------
job.cpp | 17 +++++++++--------
1 file changed, 9 insertions(+), 8 deletions(-)