Robot Framework 7.0 changes

Update robot code syntax overall in the repo

Changes:
   - Update the requirement.txt package version for robot
   - The '[Return]' setting is deprecated.
      Use the 'RETURN' statement instead.
   - Singular section headers like '*** Test Case ***'
     are deprecated. Use plural format like
     '*** Test Cases ***' instead.
   - Singular section headers like '*** Variable ***'
     are deprecated

Tested:
   - Ran from sandbox with the version
     $ robot --version
     Robot Framework 7.0 (Python 3.10.12 on linux)

     and also tested on latest python version

     Robot Framework 7.0 (Python 3.11.9 on linux)

Change-Id: I54e85f9d799556c63b9a39f79483f83e9b980768
Signed-off-by: George Keishing <gkeishin@in.ibm.com>
diff --git a/ipmi/dcmi/test_dcmi_asset_tag.robot b/ipmi/dcmi/test_dcmi_asset_tag.robot
index 7c6af70..d8959c6 100644
--- a/ipmi/dcmi/test_dcmi_asset_tag.robot
+++ b/ipmi/dcmi/test_dcmi_asset_tag.robot
@@ -104,7 +104,7 @@
     Set Test Variable  ${random_string}
     Set Test Variable  ${number_of_bytes_to_write}
 
-    [Return]  ${ret}
+    RETURN  ${ret}
 
 Get Raw Asset Tag
     [Documentation]  Get asset tag command in raw command.
@@ -112,7 +112,7 @@
     ${cmd}=  Catenate  ${DCMI_RAW_CMD['DCMI']['Asset_Tag'][0]} 0x${number_of_bytes_to_write}
     ${ret}=  Run IPMI Command  ${cmd}
 
-    [Return]  ${ret}
+    RETURN  ${ret}
 
 Validate Asset Tag Via Raw Command
     [Documentation]  Validate asset tag via raw cmd.
@@ -136,4 +136,4 @@
     ...  '${length_1}' != '1'  ${length}
     ${ret}=  Convert To Lower Case  ${length_2}
 
-    [Return]  ${ret}
+    RETURN  ${ret}