Nits and stuff

[webbnh]

This PR is a small collection of tiny fixes for things which I've hit in various contexts:

• run-server-func-tests contains a couple of definitions which appear to be unused.
• datasets_inventory.py contains a docstring which was missed when I reworked tar file extraction.
• The regex in the Agent container Makefile used to extract the version number from the RPM file name doesn't work properly if the "revision" number is missing (it requires the second dot which would be omitted when the third number is omitted).

The last issue was causing some misbehavior in the b0.73 branch build (but Nick is going to fix that by adding the "revision" number).