Scripts are not properly recognized in many cases

[dgarijo]

The second evaluation uncovers that many repos that have scripts deemed as important are not detected.

I think there are problems which are filtering the availability of such files as part of the software_invocation list.

[dgarijo]

After the last improvements, there are still many repos with scripts missing.

[dgarijo]

Now some are missing because they are misclassified as tests (see #311).
Others are still not recognized (scripts with body but not main are ignored)