Update for python 3.12 and remove cython<3 pinning

Author: kburns

.github/workflows/test_conda_builds.yml

@@ -69,7 +69,7 @@ jobs:
           conda activate dedalus2
           conda env config vars set OMP_NUM_THREADS=1
           conda env config vars set NUMEXPR_MAX_THREADS=1
-          conda install -y -c conda-forge dedalus c-compiler "h5py=*=mpi*" "cython<3.0"
+          conda install -y -c conda-forge dedalus c-compiler cython "h5py=*=mpi*"
           conda uninstall -y --force dedalus
           CC=mpicc pip3 install --no-cache --no-build-isolation http://github.com/dedalusproject/dedalus/zipball/v2_master/
       - name: Test build
@@ -103,7 +103,7 @@ jobs:
           conda activate dedalus3
           conda env config vars set OMP_NUM_THREADS=1
           conda env config vars set NUMEXPR_MAX_THREADS=1
-          conda install -y -c conda-forge dedalus c-compiler "h5py=*=mpi*" "cython<3.0"
+          conda install -y -c conda-forge dedalus c-compiler cython "h5py=*=mpi*"
           conda uninstall -y --force dedalus
           CC=mpicc pip3 install --no-cache --no-build-isolation http://github.com/dedalusproject/dedalus/zipball/master/
       - name: Test build

conda_install_dedalus2.sh

@@ -36,7 +36,7 @@ INSTALL_HDF5=1
 BLAS="openblas"
 
 # Python version
-PYTHON_VERSION="3.10"
+PYTHON_VERSION="3.12"
 
 # Install native arm64 build on Apple Silicon
 # Note: Only relevent on Apple Silicon machines, where native arm64 builds may exhibit errors
@@ -151,7 +151,7 @@ conda config --add channels conda-forge
 conda config --set channel_priority strict
 
 echo "Installing conda-forge python, pip, wheel, setuptools, cython"
-conda install "${CARGS[@]}" "python=${PYTHON_VERSION}" pip wheel setuptools "cython<3.0"
+conda install "${CARGS[@]}" "python=${PYTHON_VERSION}" pip wheel setuptools cython
 
 case "${BLAS}" in
 "openblas")

conda_install_dedalus3.sh

@@ -36,7 +36,7 @@ INSTALL_HDF5=1
 BLAS="openblas"
 
 # Python version
-PYTHON_VERSION="3.10"
+PYTHON_VERSION="3.12"
 
 # Install native arm64 build on Apple Silicon
 # Note: Only relevent on Apple Silicon machines, where native arm64 builds may exhibit errors
@@ -151,7 +151,7 @@ conda config --add channels conda-forge
 conda config --set channel_priority strict
 
 echo "Installing conda-forge python, pip, wheel, setuptools, cython"
-conda install "${CARGS[@]}" "python=${PYTHON_VERSION}" pip wheel setuptools "cython<3.0"
+conda install "${CARGS[@]}" "python=${PYTHON_VERSION}" pip wheel setuptools cython
 
 case "${BLAS}" in
 "openblas")