Computing `expval` and `var` with `LightningTensor` using `quimb` MPS #4655

Job	Run time
Python tests (ubuntu-22.04, lightning_qubit)	54m 22s
C++ tests (ubuntu-22.04, lightning_qubit)	18m 14s
C++ tests (OpenBLAS) (ubuntu-22.04, lightning_qubit)	8m 51s
Python tests with OpenBLAS (ubuntu-22.04, lightning_qubit)	11m 14s
Build and cache Kokkos / Set Kokkos builder matrix	1s
Build and cache Kokkos / Kokkos core (SERIAL)	3s
Build and cache Kokkos / Kokkos core (OPENMP)	2s
C++ tests (Kokkos) (ubuntu-22.04, lightning_kokkos, SERIAL, 4.2.00)	5m 1s
C++ tests (multiple backends) (ubuntu-22.04, SERIAL, 4.2.00)	5m 21s
C++ tests (Kokkos) (ubuntu-22.04, lightning_kokkos, OPENMP, 4.2.00)	5m 9s
Python tests with Kokkos (ubuntu-22.04, lightning_kokkos, SERIAL, 4.2.00)	59m 44s
C++ tests (multiple backends) (ubuntu-22.04, OPENMP, 4.2.00)	5m 30s
Python tests with Kokkos (ubuntu-22.04, lightning_kokkos, OPENMP, 4.2.00)	1h 0m 12s
Python tests with Kokkos (ubuntu-22.04, all, SERIAL, 4.2.00)	14m 29s
Python tests with Kokkos (ubuntu-22.04, all, OPENMP, 4.2.00)	14m 10s
Upload cpp coverage data to codecov	8s
Upload python coverage data to codecov	0s
	4h 22m 31s

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