doc: removing biblio keywords (that are not shown anyway) to please new Sphinx version

10 jobs for BioEM-2.0.3 in 1 minute and 4 seconds (queued for 1 second)
latest
Status Job ID Name Coverage
  Build
passed #708730
build-gcc-mpi

00:00:07

passed #708732
build-gcc-mpi-cuda

00:00:21

passed #708731
build-gcc-mpi-test

00:00:09

38.0%
passed #708733
build-intel-mpi

00:00:06

 
  Tests
passed #708734
verify_options

00:00:04

passed #708736
verify_probabilities

00:00:04

passed #708735
verify_tutorial

00:00:04

 
  Coverage
passed #708737
total_coverage

00:00:05

75.5%
 
  Deploy
passed #708738
pages

00:00:00

passed pages:deploy

00:00:00