Decouple einsum utils function to separate file (#1920)

* Update LinAlg functions from BLAS routine

* Decouple einsum utils function to separate file

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Co-authored-by: vtavana <[email protected]>

Author: antonwolfy

dpnp/dpnp_iface_linearalgebra.py

@@ -43,9 +43,9 @@
 
 import dpnp
 
+from .dpnp_utils.dpnp_utils_einsum import dpnp_einsum
 from .dpnp_utils.dpnp_utils_linearalgebra import (
     dpnp_dot,
-    dpnp_einsum,
     dpnp_kron,
     dpnp_matmul,
 )