[Binding/Sofa.Core] Update MechanicalObject Target in test

[fredroy]

To merge in the same time as sofa-framework/sofa#2766

[guparan]

1 unit test is failing @fredroy

[ RUN      ] SofaPython3/Sofa.all_tests/75_Sofa_Core_BaseObject_test_getTarget
======================================================================
FAIL: test_getTarget (BaseObject.Test)
----------------------------------------------------------------------
Traceback (most recent call last):
  File "BaseObject.py", line 58, in test_getTarget
    self.assertEqual(c.getTarget(), 'Sofa.Component.Container')
AssertionError: 'SofaBaseMechanics' != 'Sofa.Component.Container'
- SofaBaseMechanics
+ Sofa.Component.Container


----------------------------------------------------------------------
Ran 1 test in 0.001s

FAILED (failures=1)
/home/runner/work/SofaPython3/SofaPython3/artifact/bin/Bindings.Sofa.Tests.d/Core/BaseObject.py:0: Failure
Failed
[  FAILED  ] SofaPython3/Sofa.all_tests/75_Sofa_Core_BaseObject_test_getTarget, where GetParam() = /home/runner/work/SofaPython3/SofaPython3/artifact/bin/Bindings.Sofa.Tests.d/Core/BaseObject.py with args {test_getTarget, } (2 ms)

Looks like the test itself should be modified, am I right?

[guparan]

See my comment above 👍

[guparan]

My bad, this PR aims to fix a future change in SOFA (see sofa-framework/sofa#2766)