[DOCS] Create stubbed files for the creating_and_editing_expectations section of the how-to guides.

[abegong]

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Changes proposed in this pull request:

• This PR creates stubbed files for the creating_and_editing_expectations section of the how-to guides.

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[coveralls]

Coverage remained the same at 72.415% when pulling f51934e on docs/rationalize_how_to_create_and_edit_expectations into ef289ea on develop.

[codecov]

Codecov Report

Merging #1493 into develop will decrease coverage by 0.01%.
The diff coverage is n/a.

@@             Coverage Diff             @@
##           develop    #1493      +/-   ##
===========================================
- Coverage    76.91%   76.90%   -0.02%     
===========================================
  Files          130      130              
  Lines        14787    14787              
===========================================
- Hits         11374    11372       -2     
- Misses        3413     3415       +2     

Impacted Files	Coverage Δ
...ctations/core/usage_statistics/usage_statistics.py	81.06% <0.00%> (-0.98%)	⬇️

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[eugmandel]

@abegong Let's add the Prerequisites info box from #1491

[abegong]

I don't think it makes sense to gate on that change.

1. [DOCS] Added a Prerequisites info box to the how-to guide template #1491 hasn't even been merged yet.
2. These are stubs. They don't have prerequisites. Once we actually writing the articles, they should include Prerequisites. But not the stubs.

[eugmandel]

I don't think it makes sense to gate on that change.

1. [DOCS] Added a Prerequisites info box to the how-to guide template #1491 hasn't even been merged yet.
2. These are stubs. They don't have prerequisites. Once we actually writing the articles, they should include Prerequisites. But not the stubs.

OK. Let's not gate on this change.