treewide: Disable automatic argparse argument shortening

Disables allowing the python argparse library from automatically
shortening command line arguments, this prevents issues whereby
a new command is added and code that wrongly uses the shortened
command of an existing argument which is the same as the new
command being added will silently change script behaviour.

Signed-off-by: Jamie McCrae <jamie.mccrae@nordicsemi.no>
diff --git a/scripts/set_assignees.py b/scripts/set_assignees.py
index 15564f0..a636098 100755
--- a/scripts/set_assignees.py
+++ b/scripts/set_assignees.py
@@ -24,7 +24,7 @@
     global args
     parser = argparse.ArgumentParser(
         description=__doc__,
-        formatter_class=argparse.RawDescriptionHelpFormatter)
+        formatter_class=argparse.RawDescriptionHelpFormatter, allow_abbrev=False)
 
     parser.add_argument("-M", "--maintainer-file", required=False, default="MAINTAINERS.yml",
                         help="Maintainer file to be used.")