Merge pull request #3335 from jepler/fix-doc-build

conf.py (docs): Reorder the steps of the doc build

conf.py

@@ -42,6 +42,9 @@ master_doc = 'docs/index'
 # Grab the JSON values to use while building the module support matrix
 # in 'shared-bindings/index.rst'
 
+# The stubs must be built before we calculate the shared bindings matrix
+subprocess.check_output(["make", "stubs"])
+
 #modules_support_matrix = shared_bindings_matrix.support_matrix_excluded_boards()
 modules_support_matrix = shared_bindings_matrix.support_matrix_by_board()
 
@@ -77,7 +80,6 @@ source_suffix = {
     '.md': 'markdown',
 }
 
-subprocess.check_output(["make", "stubs"])
 extensions.append('autoapi.extension')
 
 autoapi_type = 'python'