General doc updates

Added missing doc, for example for serial tests, fixed 404 links,
spellings, formatting and etc

Change-Id: I07a8cf9508d3cba33bd04afdc301bb7145153d59
diff --git a/tox.ini b/tox.ini
index de81707..7c50a3b 100644
--- a/tox.ini
+++ b/tox.ini
@@ -359,8 +359,9 @@
   sphinx-apidoc -f -o doc/source/tests/image tempest/api/image
   sphinx-apidoc -f -o doc/source/tests/network tempest/api/network
   sphinx-apidoc -f -o doc/source/tests/object_storage tempest/api/object_storage
-  sphinx-apidoc -f -o doc/source/tests/scenario tempest/scenario
   sphinx-apidoc -f -o doc/source/tests/volume tempest/api/volume
+  sphinx-apidoc -f -o doc/source/tests/scenario tempest/scenario
+  sphinx-apidoc -f -o doc/source/tests/serial_tests tempest/serial_tests
   rm -rf doc/build
   sphinx-build -W -b html doc/source doc/build/html
 allowlist_externals =
@@ -377,8 +378,9 @@
    sphinx-apidoc -f -o doc/source/tests/image tempest/api/image
    sphinx-apidoc -f -o doc/source/tests/network tempest/api/network
    sphinx-apidoc -f -o doc/source/tests/object_storage tempest/api/object_storage
-   sphinx-apidoc -f -o doc/source/tests/scenario tempest/scenario
    sphinx-apidoc -f -o doc/source/tests/volume tempest/api/volume
+   sphinx-apidoc -f -o doc/source/tests/scenario tempest/scenario
+   sphinx-apidoc -f -o doc/source/tests/serial_tests tempest/serial_tests
    sphinx-build -W -b latex doc/source doc/build/pdf
    make -C doc/build/pdf