TCK: remove reference comparison for TapChangers step

[AbdelHedhili]

Please check if the PR fulfills these requirements

• [x] The commit message follows our guidelines
• [x] Tests for the changes have been added (for bug fixes / features)
• [ ] Docs have been added / updated (for bug fixes / features)

What kind of change does this PR introduce? There are tests that compare Ratio/PhaseTapChanger steps by reference and expect that we keep the same reference for these objects

What is the current behavior? Reference comparison for steps in TCK

What is the new behavior (if this is a feature change)? No more Reference comparison for steps in TCK

[sonarcloud[bot]]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarCloud