Invoke config.py instead of config.pl in reverted content

perl -i -pe 's/\bconfig\.pl/config.py/g' $(git grep -l -Fw config.pl
-- . '#!tests/scripts/test_config_script.py')
diff --git a/tests/scripts/key-exchanges.pl b/tests/scripts/key-exchanges.pl
index 3bf7ae3..be029c7 100755
--- a/tests/scripts/key-exchanges.pl
+++ b/tests/scripts/key-exchanges.pl
@@ -47,10 +47,10 @@
     print "******************************************\n";
 
     # full config with all key exchanges disabled except one
-    system( "scripts/config.pl full" ) and abort "Failed config full\n";
+    system( "scripts/config.py full" ) and abort "Failed config full\n";
     for my $k (@kexes) {
         next if $k eq $kex;
-        system( "scripts/config.pl unset $k" )
+        system( "scripts/config.py unset $k" )
             and abort "Failed to disable $k\n";
     }