fix(test): SSynchronizer test fails randomly
Description
The SSynchronizer test fails randomly.
The log of the crash highlight the copyMatrixFromTLtoOutput method, where the buffer lock is scoped, while the buffer is taken out of the scope.
THis can lead to concurrent access to the buffer and be the origin of the crash.
Steps to reproduce
Run the module_syncTest a lot of time. There are some segfault which happens randomly.
Functional specifications
there should not be any crash.
Technical specifications
extend the buffer lock in both copyMatrixFromTLtoOutput and copyFrameFromTLtoOutput to cover the whole method.
Indeed, the lock scope was reduced to prevent locking the frame TL too long. However, the method in itself is already a subpart of the whole synchronization process, and it should be fine in terms of performance to lock the buffer for the whole copyFrameFromTLtoOutput and copyMatrixFromTLtoOutput methods.
Test plan
Run the module_syncTest a lot of time