Fix typo in test documentation

Change-Id: I884c3c2bc41cd201baab58f0d32f16807e7380f9
Signed-off-by: George Keishing <gkeishin@in.ibm.com>
diff --git a/openpower/vpd/test_vpd_tool.robot b/openpower/vpd/test_vpd_tool.robot
index 277861e..29e0b73 100644
--- a/openpower/vpd/test_vpd_tool.robot
+++ b/openpower/vpd/test_vpd_tool.robot
@@ -50,7 +50,7 @@
 
 
 Verify VPD Field Write
-    [Documentation]  Verify writting VPD field value via vpdtool.
+    [Documentation]  Verify writing VPD field value via vpdtool.
     [Tags]  Verify_VPD_Field_Write
 
     ${components}=  Get Dictionary Keys  ${VPD_DETAILS}