Initialize test_v2d.py variables

[darbyjohnston]

I have been seeing occasional CI failures with this error:

======================================================================
FAIL: test_serialization_round_trip (test_v2d.V2dTests.test_serialization_round_trip)
----------------------------------------------------------------------
Traceback (most recent call last):
  File "D:/a/OpenTimelineIO/OpenTimelineIO/tests/test_v2d.py", line 112, in test_serialization_round_trip
    self.assertEqual(v2d, deserialized)
AssertionError: otio.schema.V2d(x=1.2375583497411374e+214, y=3.503154865959304e+151) != otio.schema.V2d(x=1.2375583497411374e+214, y=3.5031548659593044e+151)

----------------------------------------------------------------------
Ran 489 tests in 13.798s

FAILED (failures=1, skipped=2)
make: *** [Makefile:79: coverage-core] Error 1
Error: Process completed with exit code 2.

It looks like the variables being used are not initialized, causing them to have random values that can trigger the failure. I'm not sure why the serialization is failing but we should probably initialize the values so the tests are consistent.

[codecov-commenter]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 85.00%. Comparing base (c0e97b0) to head (e694108).
⚠️ Report is 75 commits behind head on main.

❌ Your changes status has failed because you have indirect coverage changes. Learn more about Unexpected Coverage Changes and reasons for indirect coverage changes.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #1955      +/-   ##
==========================================
+ Coverage   84.11%   85.00%   +0.88%     
==========================================
  Files         198      181      -17     
  Lines       22241    13074    -9167     
  Branches     4687     1206    -3481     
==========================================
- Hits        18709    11113    -7596     
+ Misses       2610     1778     -832     
+ Partials      922      183     -739     

Flag	Coverage Δ
py-unittests	85.00% <100.00%> (+0.88%)	⬆️

Flags with carried forward coverage won't be shown. Click here to find out more.

Files with missing lines	Coverage Δ
tests/test_v2d.py	97.46% <100.00%> (+0.36%)	⬆️

... and 139 files with indirect coverage changes

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[apetrynet]

Good catch!
Sneaky bug indeed.

However, should we look into why an uninitialized v2d gets a random value? I would think the serialized value of an "empty" v2d should be null, [] or even [0,0]?
Perhaps we should look at the otio implementation of v2d? I assume the random values stem from old data in memory at some location, but I'm in no way a C++ expert