patch 8.2.2881: various pieces of code not covered by tests

Problem:    Various pieces of code not covered by tests.
Solution:   Add a few more tests. (Yegappan Lakshmanan, closes #8245)
diff --git a/src/testdir/test_python3.vim b/src/testdir/test_python3.vim
index 1e9ef82..66d5db5 100644
--- a/src/testdir/test_python3.vim
+++ b/src/testdir/test_python3.vim
@@ -511,6 +511,8 @@
   10new
   py3 vim.current.window.height = 5
   call assert_equal(5, winheight(0))
+  py3 vim.current.window.height = 3.2
+  call assert_equal(3, winheight(0))
 
   " Test for setting the window width
   10vnew