Replace hoc_regexp_* by std::regex #7129

Job	Run time
macOS-12 - setuptools (CC=gcc-9 CXX=g++-9)	15m 25s
macOS-12 - cmake (CC=gcc-10 CXX=g++-10)	14m 41s
macOS-12 - cmake (CC=gcc-10 CXX=g++-10)	15m 28s
macOS-12 - cmake (-DNRN_ENABLE_CORENEURON=ONCC=gcc-9 CXX=g++-9)	15m 20s
macOS-12 - cmake (-DNRN_ENABLE_MPI=OFF -DNRN_ENABLE_INTERVIEWS=OFF -DNRN_ENABLE_CORENEURON=ONCC=gcc-9 CXX=g++-9)	11m 54s
macOS-12 - cmake (-DNRN_ENABLE_PYTHON=OFF -DNRN_ENABLE_RX3D=OFF -DNRN_ENABLE_CORENEURON=ONCC=gcc-10 CXX=g++-10)	11m 28s
ubuntu-20.04 - setuptools (CC=gcc-9 CXX=g++-9)	7m 11s
ubuntu-20.04 - cmake (CC=gcc-10 CXX=g++-10)	8m 37s
ubuntu-20.04 - cmake (CC=gcc-10 CXX=g++-10)	9m 31s
ubuntu-20.04 - cmake (-DNRN_ENABLE_CORENEURON=ONCC=gcc-9 CXX=g++-9)	8m 53s
ubuntu-20.04 - cmake (-DNRN_ENABLE_MPI=OFF -DNRN_ENABLE_INTERVIEWS=OFF -DNRN_ENABLE_CORENEURON=ONCC=gcc-9 CXX=g++-9)	5m 51s
ubuntu-20.04 - cmake (-DNRN_ENABLE_PYTHON=OFF -DNRN_ENABLE_RX3D=OFF -DNRN_ENABLE_CORENEURON=ONCC=gcc-10 CXX=g++-10)	4m 3s
ubuntu-22.04 - cmake (-DNRN_ENABLE_CORENEURON=ON -DNRN_ENABLE_INTERVIEWS=OFF -DNMODL_SANITIZERS=undefinedundefined)	10m 8s
ubuntu-22.04 - cmake (-DNRN_ENABLE_CORENEURON=ON -DNRN_ENABLE_INTERVIEWS=OFF -DNMODL_SANITIZERS=addressaddress)	9m 43s
ubuntu-22.04 - cmake (-DNRN_ENABLE_CORENEURON=ON -DNRN_ENABLE_MPI=OFF -DCORENRN_ENABLE_OPENMP=OFF -DNRN_ENABLE_RX3D=OFFthread)	22m 22s
macOS-13 - cmake (-DNRN_ENABLE_CORENEURON=ON -DNRN_ENABLE_INTERVIEWS=OFF -DNRN_ENABLE_RX3D=OFF -DNMODL_SANITIZERS=addressaddress)	12m 50s
Final CI	1s
	3h 3m 26s

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