Merge branch 'SPHINX_4'

diff --cc sphinx-pdg.spec
index 8695c1560c78adfc7a18b63e878b5e3d990d8016,899ea72411b6ba74edc7422c5e26138952ef1bfc..aeb4c7b65a9cd21b902a5d3a0e57038100950eec
--- 1/sphinx-pdg.spec
--- 2/sphinx-pdg.spec
+++ b/sphinx-pdg.spec
@@@ -55,28 -59,28 +59,35 @@@ BuildRequires:     python3-snowballstemmer 
  BuildRequires:        python3-sphinxcontrib-applehelp
  BuildRequires:        python3-sphinxcontrib-devhelp
  BuildRequires:        python3-sphinxcontrib-jsmath
- BuildRequires:        python3-sphinxcontrib-htmlhelp
- BuildRequires:        python3-sphinxcontrib-serializinghtml
+ BuildRequires:        python3-sphinxcontrib-htmlhelp >= 2.0.0
+ BuildRequires:        python3-sphinxcontrib-serializinghtml >= 1.1.5
  BuildRequires:        python3-sphinxcontrib-qthelp
 -%if "%{_ver_lt '%{py3_ver}' '3.8'}" == "1"
 -BuildRequires:        python3-typed_ast
 -%endif
  %endif
  %if %{with doc}
- BuildRequires:        python3-docutils
 +BuildRequires:        python3-alabaster >= 0.7
 +BuildRequires:        python3-alabaster < 0.8
+ BuildRequires:        python3-docutils >= 0.14
+ BuildRequires:        python3-docutils < 0.19
 +BuildRequires:        python3-imagesize
+ %if "%{_ver_lt '%{py3_ver}' '3.10'}" == "1"
+ BuildRequires:        python3-importlib_metadata >= 4.4
+ %endif
 +BuildRequires:        python3-jinja2 >= 2.3
 +BuildRequires:        python3-packaging
 +BuildRequires:        python3-pygments
 +BuildRequires:        python3-requests >= 2.5.0
  BuildRequires:        python3-sphinxcontrib-applehelp
  BuildRequires:        python3-sphinxcontrib-devhelp
- BuildRequires:        python3-sphinxcontrib-htmlhelp
+ BuildRequires:        python3-sphinxcontrib-htmlhelp >= 2.0.0
  BuildRequires:        python3-sphinxcontrib-qthelp
- BuildRequires:        python3-sphinxcontrib-serializinghtml
+ BuildRequires:        python3-sphinxcontrib-serializinghtml >= 1.1.5
  BuildRequires:        python3-sphinxcontrib-websupport
++%if "%{_ver_lt '%{py3_ver}' '3.8'}" == "1"
++BuildRequires:        python3-typed_ast
++%endif
  %endif
  BuildRequires:        rpm-pythonprov
- BuildRequires:        rpmbuild(macros) >= 1.714
+ BuildRequires:        rpmbuild(macros) >= 1.749
  BuildRequires:        sed >= 4.0
  %if %{with tests}
  # for test_build_latex.py (disabled now)