CircleCI: stop upgrading pyenv #7241

Job	Run time
macOS-12 - setuptools (CC=gcc-9 CXX=g++-9)	14m 26s
macOS-12 - cmake (CC=gcc-10 CXX=g++-10)	18m 1s
macOS-12 - cmake (CC=gcc-10 CXX=g++-10)	25m 15s
macOS-12 - cmake (-DNRN_ENABLE_CORENEURON=ONCC=gcc-9 CXX=g++-9)	16m 56s
macOS-12 - cmake (-DNRN_ENABLE_MPI=OFF -DNRN_ENABLE_INTERVIEWS=OFF -DNRN_ENABLE_CORENEURON=ONCC=gcc-9 CXX=g++-9)	12m 6s
macOS-12 - cmake (-DNRN_ENABLE_PYTHON=OFF -DNRN_ENABLE_RX3D=OFF -DNRN_ENABLE_CORENEURON=ONCC=gcc-10 CXX=g++-10)	12m 51s
ubuntu-20.04 - setuptools (CC=gcc-9 CXX=g++-9)	6m 26s
ubuntu-20.04 - cmake (CC=gcc-10 CXX=g++-10)	8m 25s
ubuntu-20.04 - cmake (CC=gcc-10 CXX=g++-10)	10m 9s
ubuntu-20.04 - cmake (-DNRN_ENABLE_CORENEURON=ONCC=gcc-9 CXX=g++-9)	9m 7s
ubuntu-20.04 - cmake (-DNRN_ENABLE_MPI=OFF -DNRN_ENABLE_INTERVIEWS=OFF -DNRN_ENABLE_CORENEURON=ONCC=gcc-9 CXX=g++-9)	6m 10s
ubuntu-20.04 - cmake (-DNRN_ENABLE_PYTHON=OFF -DNRN_ENABLE_RX3D=OFF -DNRN_ENABLE_CORENEURON=ONCC=gcc-10 CXX=g++-10)	3m 55s
ubuntu-22.04 - cmake (-DNRN_ENABLE_CORENEURON=ON -DNRN_ENABLE_INTERVIEWS=OFF -DNMODL_SANITIZERS=undefinedundefined)	9m 42s
ubuntu-22.04 - cmake (-DNRN_ENABLE_CORENEURON=ON -DNRN_ENABLE_INTERVIEWS=OFF -DNMODL_SANITIZERS=addressaddress)	10m 37s
ubuntu-22.04 - cmake (-DNRN_ENABLE_CORENEURON=ON -DNRN_ENABLE_MPI=OFF -DCORENRN_ENABLE_OPENMP=OFF -DNRN_ENABLE_RX3D=OFFthread)	23m 43s
macOS-13 - cmake (-DNRN_ENABLE_CORENEURON=ON -DNRN_ENABLE_INTERVIEWS=OFF -DNRN_ENABLE_RX3D=OFF -DNMODL_SANITIZERS=addressaddress)	16m 22s
Final CI	1s
	3h 24m 12s

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