CI: fix envvars in image for openmpi

Author: caic99

Dockerfile.gnu

@@ -1,7 +1,7 @@
 FROM debian:bullseye-slim
 
 RUN apt-get update && apt-get install -y --no-install-recommends libopenblas-dev liblapack-dev libscalapack-mpi-dev git g++ gfortran libssl-dev make cmake vim wget bc unzip python3-numpy
-ENV OMPI_ALLOW_RUN_AS_ROOT=1 OMPI_ALLOW_RUN_AS_ROOT_CONFIRM=1
+ENV OMPI_ALLOW_RUN_AS_ROOT=1 OMPI_ALLOW_RUN_AS_ROOT_CONFIRM=1 OMPI_MCA_btl_vader_single_copy_mechanism=none
 
 ENV GIT_SSL_NO_VERIFY=1 TERM=xterm-256color