Add Snell's Law refraction algorithm

[Dsannue]

• I have read CONTRIBUTING.md.
• This pull request is all my own work -- I have not plagiarized it.
• All filenames are in PascalCase.
• All functions and variable names follow Java naming conventions.
• All new algorithms have a URL in their comments that points to Wikipedia or other similar explanations.
• All new code is formatted with clang-format -i --style=file path/to/your/file.java

[DenizAltunkapan]

@Dsannue please fix the failing workflows

[codecov-commenter]

Codecov Report

❌ Patch coverage is 71.42857% with 2 lines in your changes missing coverage. Please review.
✅ Project coverage is 78.62%. Comparing base (246162e) to head (9f0d15d).

Files with missing lines	Patch %	Lines
.../main/java/com/thealgorithms/physics/SnellLaw.java	71.42%	2 Missing ⚠️

Additional details and impacted files

@@             Coverage Diff              @@
##             master    #7150      +/-   ##
============================================
- Coverage     78.62%   78.62%   -0.01%     
- Complexity     6823     6825       +2     
============================================
  Files           765      766       +1     
  Lines         22600    22607       +7     
  Branches       4443     4444       +1     
============================================
+ Hits          17769    17774       +5     
- Misses         4117     4119       +2     
  Partials        714      714              

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