Remove some unnecessary indirection in job definitions.

Remove some unnecessary indirection in job definitions.

Some job templates were only used once or only existed to extend a
single parent. Other templates became trivial when accounting for
job parameter merging behavior. Additionally, removed some ineffective
or unnecessary parameter or variable specifications.

Note: in the case of the 'configure' jobs, KUBERNETES variables that
were previously masked by job inheritance are now exposed, in accordance
with the apparent original intent.

Change-Id: Idd4100d729a08c47b83c42ca9d7e0257a4029c6f