code_update_utils: s/delete/Delete

The method name is Delete, not delete.

Tested: Verified the Delete_Host_Image was successful.

Change-Id: Iba19f1ea8809714e40bbbc6787e37ff2589904d4
Signed-off-by: Adriana Kobylak <anoo@us.ibm.com>
diff --git a/lib/code_update_utils.robot b/lib/code_update_utils.robot
index 915e28d..034e5c8 100644
--- a/lib/code_update_utils.robot
+++ b/lib/code_update_utils.robot
@@ -333,7 +333,7 @@
 
     ${arglist}=  Create List
     ${args}=  Create Dictionary  data=${arglist}
-    ${resp}=  OpenBMC Post Request  ${software_object}/action/delete
+    ${resp}=  OpenBMC Post Request  ${software_object}/action/Delete
     ...  data=${args}
     Should Be Equal As Strings  ${resp.status_code}  ${HTTP_OK}