Reorganize the CI and remove the unused part

[yhmtsai]

This is preparation for CI manager to make the auto generation targets clear.

This also bump the minimal version requirement of gtest from 1.10.0 to 1.12.0 from google/googletest#3797
We had this to workaround that before

# fix gtest issue https://github.com/google/googletest/issues/3514
CXX_FLAGS: "-Wno-error=maybe-uninitialized"

[ginkgo-bot]

Error: The following files need to be formatted:

benchmark/solver/distributed/solver.cpp
benchmark/spmv/distributed/spmv.cpp
benchmark/utils/generator.hpp
common/cuda_hip/distributed/matrix_kernels.cpp
core/device_hooks/common_kernels.inc.cpp
core/distributed/helpers.hpp
core/distributed/matrix.cpp
core/distributed/matrix_kernels.hpp
core/distributed/preconditioner/schwarz.cpp
core/solver/direct.cpp
core/test/config/solver.cpp
core/test/mpi/distributed/matrix.cpp
core/test/mpi/distributed/solver/multigrid.cpp
core/test/solver/direct.cpp
cuda/base/types.hpp
dpcpp/distributed/matrix_kernels.dp.cpp
include/ginkgo/core/distributed/matrix.hpp
include/ginkgo/core/distributed/preconditioner/schwarz.hpp
include/ginkgo/core/multigrid/pgm.hpp
include/ginkgo/core/solver/direct.hpp
omp/distributed/matrix_kernels.cpp
reference/distributed/matrix_kernels.cpp
reference/test/distributed/matrix_kernels.cpp
test/distributed/matrix_kernels.cpp
test/mpi/distributed/matrix.cpp
test/mpi/multigrid/pgm.cpp
test/mpi/preconditioner/schwarz.cpp
test/solver/direct.cpp

You can find a formatting patch under Artifacts here or run format! if you have write access to Ginkgo