Test Shipping related models and schema

[Jeshan7]

Why?

In Shipping_category (Model)

• Test for get_with_rules/1 was not present.

  In Shipping_method (Model)

• Tests for get/1, get_all/0, delete/1 and for_package_query/2 were not present.

  In ShippingRuleIdentifier (Schema)

• The test file was not present.

  Shipping identifier schema file name was wrong.

This change addresses the need by:

In Shipping_category (Model)

• Added test for get_with_rules/1.

  In Shipping_method (Model)

• Added tests for get/1, get_all/0, delete/1 and for_package_query/2 .

  In ShippingRuleIdentifier (Schema)

• Created a new test file.

  Renamed the file schema/shipping_rules/shipping_rule_idenitifier.ex to schema/shipping_rules/shipping_rule_identifier.ex

[delivers #163586461]

Checklist

• [ ] I have read CONTRIBUTING.md.
• [ ] My code follows the style guidelines of this project.
• [ ] I have commented my code, particularly in hard-to-understand areas.
• [ ] My code does not generate any (new) credo and compile-time warnings.
• [ ] I have updated the documentation wherever necessary.
• [ ] I have added tests to cover my changes.

[codecov[bot]]

Codecov Report

Merging #460 into develop will increase coverage by 0.68%. The diff coverage is 100%.

@@             Coverage Diff             @@
##           develop     #460      +/-   ##
===========================================
+ Coverage    78.98%   79.67%   +0.68%     
===========================================
  Files          176      176              
  Lines         2208     2209       +1     
===========================================
+ Hits          1744     1760      +16     
+ Misses         464      449      -15

Impacted Files	Coverage Δ
.../schema/shipping_rules/shipping_rule_identifier.ex	100% <ø> (ø)
...itch_core/lib/core/data/model/shipping_category.ex	100% <100%> (+66.66%)	:arrow_up:
...s/snitch_core/lib/core/data/model/shipping_rule.ex	100% <100%> (+100%)	:arrow_up:
..._core/lib/core/data/model/general_configuration.ex	72.72% <0%> (+9.09%)	:arrow_up:
...snitch_core/lib/core/data/model/shipping_method.ex	100% <0%> (+30%)	:arrow_up:

---

Continue to review full report at Codecov.

Legend - Click here to learn more Δ = absolute <relative> (impact), ø = not affected, ? = missing data Powered by Codecov. Last update 9f5b95a...a810288. Read the comment docs.