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/openpower/pel/test_bmc_pel.robot b/openpower/pel/test_bmc_pel.robot
index 3c0ae78..aa2dbb3 100644
--- a/openpower/pel/test_bmc_pel.robot
+++ b/openpower/pel/test_bmc_pel.robot
@@ -834,7 +834,7 @@
     # Logging disk capacity limit is set to 20MB. So calculating the log usage percentage.
     ${usage_percent}=  Evaluate  ${usage_output} / 20 * 100
 
-    [return]  ${usage_percent}
+    RETURN  ${usage_percent}
 
 
 Get PEL Log IDs
@@ -881,7 +881,7 @@
     END
     Sort List  ${pel_id_list}
 
-    [Return]  ${pel_id_list}
+    RETURN  ${pel_id_list}
 
 
 Get PEL Log Via BMC CLI
@@ -891,7 +891,7 @@
     ${ids}=  Get Dictionary Keys  ${pel_records}
     Sort List  ${ids}
 
-    [Return]  ${ids}
+    RETURN  ${ids}
 
 
 Get PEL Field Value
@@ -932,7 +932,7 @@
     ${pel_section_output}=  Get From Dictionary  ${pel_output}  ${pel_section}
     ${pel_field_output}=  Get From Dictionary  ${pel_section_output}  ${pel_field}
 
-    [Return]  ${pel_field_output}
+    RETURN  ${pel_field_output}
 
 
 Verify PEL Transmission To Host