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/lib/os_utils_config.robot b/lib/os_utils_config.robot
index 38e7c01..c70d60f 100755
--- a/lib/os_utils_config.robot
+++ b/lib/os_utils_config.robot
@@ -12,14 +12,14 @@
     ...  return_stderr=True
     Should Be Empty  ${stderr}
     Log  ${\n}version: ${version}  console=yes
-    [Return]  ${version}
+    RETURN  ${version}
 
 Get Inventory
     [Documentation]  Get system inventory.
     ${inventory}  ${stderr}=  Execute Command  lshw -short  return_stderr=True
     Should Be Empty  ${stderr}
     Log  ${\n}inventory: ${inventory}  console=yes
-    [Return]  ${inventory}
+    RETURN  ${inventory}
 
 Get Memory Count
     [Documentation]  Get Memory Count.
@@ -27,7 +27,7 @@
     ...  Execute Command  lshw -short | grep memory | wc -l  return_stderr=True
     Should Be Empty  ${stderr}
     Log  ${\n}memory count: ${memory_count}  console=yes
-    [Return]  ${memory_count}
+    RETURN  ${memory_count}
 
 Verify Memory Count
     [Documentation]  Verify memory count.
@@ -43,7 +43,7 @@
     ...  return_stderr=True
     Should Be Empty  ${stderr}
     Log  ${\n}dimm_count: ${dimm_count}  console=yes
-    [Return]  ${dimm_count}
+    RETURN  ${dimm_count}
 
 Verify Dimm Count
     [Documentation]  Verify DIMM count.