Fixed the index.rst to match joint docs requirements

4 jobs from index_fix in 34 minutes 8 seconds (queued for 59 seconds)
Status Job ID Name Coverage
  Build
passed #124063
docker
build_linux_27

34:08

72.0%
passed #124064
docker
build_linux_36

29:38

72.0%
passed #124065
macosx
build_macosx_27

21:28

72.0%
passed #124066
macosx
build_macosx_36

26:07

72.0%