Note: This is only for suppressing static check of differentiability.
The essential difficulty of this method to be differentiable persists.
Further warnings will be included in the same script.

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------------------------------------------------------------------------------------------------------------

**Context:**
`qml.ops.op_math.decompositions.two_qubit_unitary.py` is not
differentiable.
**Description of the Change:**
Will raise warning if users try call this method in differentiable way
**Benefits:**
Raise caution regarding the non-differentiability of affected program
Temporarily help prevent usage of this method in differentiable way
until full implementation in the future
**Possible Drawbacks:**
Not fully fix the affected issue.
**Related GitHub Issues:**
#6045 

**Related Shortcut Stories:**
[sc-69959]

---------

Co-authored-by: Christina Lee <christina@xanadu.ai>
Co-authored-by: Pietropaolo Frisoni <pietropaolo.frisoni@xanadu.ai>