Fixed a failed unit test

[lslezak]

• Just reset the flag back for the other tests
• Some tests failed in OBS build though it was fine locally and in Travis, probably triggered by a different test order
• The errors were:

[    4s] Failures:
[    4s] 
[    4s]   1) Yast::AddOnAddOnWorkflowInclude.media_type_selection Full medium installation with no add-ons yet not registered preselects the installation URL for the add-ons
[    4s]      Failure/Error: expect(Yast::InstURL).to receive(:installInf2Url)
[    4s] 
[    4s]        (#<Yast::InstURLClass:0x000056530fff7d10 @my_textdomain=["packager"], @installInf2Url=nil>).installInf2Url(*(any args))
[    4s]            expected: 1 time with any arguments
[    4s]            received: 0 times with any arguments
[    4s]      # ./test/add-on-workflow_test.rb:39:in `block (5 levels) in <top (required)>'
[    4s] 
[    4s]   2) Yast::AddOnAddOnWorkflowInclude.media_type_selection Full medium installation with no add-ons yet not registered returns the :finish symbol
[    4s]      Failure/Error: expect(subject.media_type_selection).to eq(:finish)
[    4s] 
[    4s]        expected: :finish
[    4s]             got: nil
[    4s] 
[    4s]        (compared using ==)
[    4s]      # ./test/add-on-workflow_test.rb:45:in `block (5 levels) in <top (required)>'

[coveralls]

Coverage remained the same at 25.075% when pulling be031bc on test_fixup into 1ef42cb on SLE-15-SP2.

[mvidner]

When I try to reproduce this reliably with

rspec ./test/add-on-workflow_test.rb

I get "uninitialized constant Yast::AddOnProduct"

[wfeldt]

I get "uninitialized constant Yast::AddOnProduct"

True, but that's also the case in master, afaics.

[wfeldt]

lgtm