Remove the 'Skip' option from Constant Test Types

[Eric Reynard]

If skipping several tests in a row, the user has a tendency to select skip for constants. When submitting the data, this leads to a "clear value if skipping test" error.

It would be great to remove the option to skip constants. (they are always present and can never really be skipped)

Related to issue 98... sorry for duplicate.

[Eric Reynard]

Duplicate