bpo-33696: Install python-docs-theme even if SPHINXBUILD is defined (GH-7242)

(cherry picked from commit 05f1c8902c78dce66aed067444e2b973221bae2b)

Co-authored-by: Andrés Delfino <adelfino@gmail.com>
diff --git a/Doc/make.bat b/Doc/make.bat
index 7ca8497..0808e0c 100644
--- a/Doc/make.bat
+++ b/Doc/make.bat
@@ -16,15 +16,16 @@
         %PYTHON% -m pip install sphinx
         if errorlevel 1 exit /B
     )
-    %PYTHON% -c "import python_docs_theme" > nul 2> nul
-    if errorlevel 1 (
-        echo Installing python-docs-theme with %PYTHON%
-        %PYTHON% -m pip install python-docs-theme
-        if errorlevel 1 exit /B
-    )
     set SPHINXBUILD=%PYTHON% -c "import sphinx, sys; sys.argv[0] = 'sphinx-build'; sys.exit(sphinx.main())"
 )
 
+%PYTHON% -c "import python_docs_theme" > nul 2> nul
+if errorlevel 1 (
+    echo Installing python-docs-theme with %PYTHON%
+    %PYTHON% -m pip install python-docs-theme
+    if errorlevel 1 exit /B
+)
+
 if not defined BLURB (
     %PYTHON% -c "import blurb" > nul 2> nul
     if errorlevel 1 (
@@ -35,9 +36,6 @@
     set BLURB=%PYTHON% -m blurb
 )
 
-if not defined SPHINXBUILD set SPHINXBUILD=sphinx-build
-if not defined BLURB set BLURB=blurb
-
 if "%1" NEQ "htmlhelp" goto :skiphhcsearch
 if exist "%HTMLHELP%" goto :skiphhcsearch