Revert "re-adding hdf5 as it seems required"

This reverts commit 2c38a835019a232acd0c37abe04c171bb5515c44.
Revert "Reducing build matrix by excluding opempi"

This reverts commit b4b79731f05b4da1ff2ba3c9b05a701c4eb0c7ad.
reducing build matrix