Remove cobertura from the jenkinsfile

[mFelgate]

What does this PR do?

• What's changed? Why were these changes made? Cobertura was deemed unnecessary by the infrastructure team, and though originally left in, it changed its line coverage rating on files that weren't altered. It was decided to remove the line publishing the report, and instead use only ccCoverage.
• How should the reviewer approach this PR, especially if manual tests are required? Make sure the Jenkinsfile is in align with the teams' standards.
• Are there relevant screenshots you can add to the PR description? No

  What ticket does this PR close?

  Connected to #174

  Checklists

Change log

• [ ] The CHANGELOG has been updated, or
• [x] This PR does not include user-facing changes and doesn't require a CHANGELOG update

Test coverage

• [ ] This PR includes new unit and integration tests to go with the code changes, or
• [x] The changes in this PR do not require tests

Documentation

• [ ] Docs (e.g. READMEs) were updated in this PR, and/or there is a follow-on issue to update docs, or
• [x] This PR does not require updating any documentation

[codeclimate[bot]]

Code Climate has analyzed commit 864ebb14 and detected 0 issues on this pull request.

The test coverage on the diff in this pull request is 100.0% (50% is the threshold).

This pull request will bring the total coverage in the repository to 83.9%.

View more on Code Climate.