Retail search samples with tests (new)

[vasilypascal]

• Added retails search samples
• Added tests
• Created Runner project, which executes the sample by it's name with the help of ExampleAttributeHelper class

[snippet-bot]

Here is the summary of changes.

You are about to add 6 region tags.

• retail/interactive-tutorial/RetailSearch.Samples/SearchSimpleQuerySample.cs:20, tag retail_search_for_products_with_query_parameter
• retail/interactive-tutorial/RetailSearch.Samples/SearchWithBoostSpecSample.cs:15, tag retail_search_product_with_boost_spec
• retail/interactive-tutorial/RetailSearch.Samples/SearchWithFacetSpecSample.cs:15, tag retail_search_product_with_facet_spec
• retail/interactive-tutorial/RetailSearch.Samples/SearchWithFilteringSample.cs:15, tag retail_search_for_products_with_filter
• retail/interactive-tutorial/RetailSearch.Samples/SearchWithOrderingSample.cs:15, tag retail_search_for_products_with_ordering
• retail/interactive-tutorial/RetailSearch.Samples/SearchWithQueryExpansionSample.cs:15, tag retail_search_for_products_with_query_expansion_specification

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[amanda-tarafa]

This looks really good.

I have some minor requests.
And also, about the pagination sample, something needs to be done there so we can test all the code. Either split the sample in three different samples or create three different methods, one for each pagination "mode" you want to show. If you think this is going to take some time, I'm happy if you remove that sample and its test from this PR, and add it in a following PR.

[amanda-tarafa]

Doing this twice means that we fetch everything from the backend twice, i.e. all pages. In this case it is better to do something like:

Suggested change

	var firstPage = searchResultPages.ToArray()[0];
	var thirdPage = searchResultPages.ToArray()[2];
	var topPages = searchResultPages.Take(3).ToList();
	var firstPage = topPages[0];
	var thirdPage = topPages[2];

[vasilypascal]

Agree. Will improve that

[vasilypascal]

Resolved.

[amanda-tarafa]

We cannot tests all of this code because it is commented.
Also we don't use commented code in documentation samples.

I think it's best if you have a sample for each of these.

[vasilypascal]

Removed the SearchWithPagination Sample for now by the agreement with @tetiana-karasova

[vasilypascal]

Resolved.

[vasilypascal]

@amanda-tarafa
Fixed tests, added commented explanation for Intervals and removed SearchWithPagination class for now.

[amanda-tarafa]

LGTM!

Thanks!

[amanda-tarafa]

Failures in CI are unrelated and being tracked in #1623.