fix: fixed pending spec formatter

[D-system]

In case of a pending spec, the third argument is not provided.

Here's a sample for the parts variable:

["./spec/models/report_spec.rb", "137"]
["./spec/models/report_spec.rb", "150", "in 'block (4 levels) in <top (required)>'"]
["./spec/rails_helper.rb", "122", "in 'block (2 levels) in <top (required)>'"]

The top entry is a pending spec.

[st0012]

Thanks for the PR, can you also add a test for this case?

[D-system]

@st0012 Thanks Stan for pointing to the right spec file. The test is added. The issue was in a fixed pending spec.

[st0012]

Thanks!