Increased test coverage for SamFileValidator

[ekazachkova]

Increased test coverage for SamFileValidator

We represent PR that contains increased test coverage for SamFileValidator class with the following changes in ValidateSamFileTest:

• Make simple refactoring for executeValidation method
• Add new test for validateBamFileTermination method
• Add new test and new data provider for validating E2 tag and U2 tag process correctness.

Also, we suggest the following changes in SamFileValidator class:

• Initialize SamFileValidator's fields by constructor instead of using default values
• Add getter for errorsByType field with package access for testing.

Checklist

• Code compiles correctly
• New tests covering changes
• All tests passing

[coveralls]

Coverage increased (+0.1%) to 69.938% when pulling be0d66c on EpamLifeSciencesTeam:epam-ls_test_coverage_SamFileValidator into 70783fc on samtools:master.

[yfarjoun]

Thanks! 👍