[4173] Add atol/rtol for unitary checks in MatrixGate

[shivanth]

Add rtol/atol for unitary checks in MatrixGate.

Fixes #4173.

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[shivanth]

@googlebot I signed it!

[balopat]

Thank you for adding this! Can you please add unit tests for the new parameters?

[balopat]

Looks good, please run check/format-incremental --apply