fix: Issue 534 transformation tests failing on some platforms

[boxanm]

Description

Summary:

The 3D Transformation utests were failing on Ubuntu Bionic with Eigen 3.3.4, in contrast to all other platforms tested with Eigen 3.4.
I added a non-zero epsilon precision value to Eigen's isApprox call for Rotation and Rotation+Scaling tests.
My guess is the two versions of Eigen treat zero epsilon precision values differently; hence the tests weren't failing with 3.4.0.
Fixes #534

Changes and type of changes (quick overview):

• Added a non-zero epsilon precision value to Eigen's isApprox in failing Transformation utest.

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Checklist:

Code related

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  (i.e.: function, class, script header, README.md)
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  (Check README.md #Contributing
  for local testing procedure using libpointmatcher-build-system)

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PR description related

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  • Breaking changes: <type>!
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    see commit_msg_reference.md
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Note for repository admins

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[sonarqubecloud]

Quality Gate failed

Failed conditions

20.6% Duplication on New Code (required ≤ 3%)

See analysis details on SonarCloud

[boxanm]

The arm64 build randomly falls on the build farm. Since this issue wasn't encountered locally on an arm machine, we assume it was due to the CPU architecture virtualization.
I'm therefore bypassing the branch protections.