OXID-56 Refactor XML Example

[TobiasGraml11]

Purpose

Add a Base Class for the example products, to be able to typehint the XML Example.

Approach

Add Base Class and extend the current example products from it.

Open Questions and Pre-Merge TODOs

• [x] composer lint and composer fix was executed.
• [x] Tests were written and pass with 100% coverage.
• [x] ~A issue with a detailed explanation of the problem/enhancement was created and linked.~ OXID-56 Story

[codecov-io]

Codecov Report

Merging #112 into develop will not change coverage. The diff coverage is n/a.

@@           Coverage Diff            @@
##             develop   #112   +/-   ##
========================================
  Coverage        100%   100%           
  Complexity       267    267           
========================================
  Files             49     49           
  Lines            701    701           
========================================
  Hits             701    701

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[howard]

@TobiasGraml11 Please fill out the PR description template to clarify the nature of this proposed change!