Test documentation typo fixes using codespell tool

Changes:
      - Fix typo in code documentation and test name

Tested: - Using codespell tool.

Change-Id: Ia1b65bddc01a4b1c103af9f2094d87da11c88953
Signed-off-by: George Keishing <gkeishin@in.ibm.com>
diff --git a/lib/dump_utils.py b/lib/dump_utils.py
index ee70850..1f00683 100755
--- a/lib/dump_utils.py
+++ b/lib/dump_utils.py
@@ -12,7 +12,6 @@
 import gen_misc as gm
 import gen_print as gp
 import gen_robot_keyword as grk
-import var_funcs as vf
 from robot.libraries.BuiltIn import BuiltIn
 
 base_path = (
@@ -107,7 +106,7 @@
     Description of argument(s):
     targ_dir_path                   The path of the directory to receive the
                                     dump files.
-    targ_file_prefix                Prefix which will be pre-pended to each
+    targ_file_prefix                Prefix which will be prepended to each
                                     target file's name.
     dump_dict                       A dump dictionary such as the one returned
                                     by get_dump_dict.  If this value is None,