drop usage of experimental switch feature

bin/account-manager.pl.in

@@ -4,8 +4,6 @@ use strict;
 use warnings;
 use utf8;
 use lib qw(@modulesdir@);
-use feature "switch";
-no if $] >= 5.017011, warnings => 'experimental::smartmatch';
 
 use Config::Tiny;
 use Data::Dumper;
@@ -62,21 +60,19 @@ AccountManager::DB->register_db(
 
 my $db = AccountManager::DB->new();
 
-for ($action) {
-    when ('add_account')    { add_account()    }
-    when ('list_accounts')  { list_accounts()  }
-    when ('add_service')    { add_service()    }
-    when ('list_services')  { list_services()  }
-    when ('add_token')      { add_token()      }
-    when ('get_token')      { get_token()      }
-    when ('list_tokens')    { list_tokens()    }
-    when ('parse_metadata') { parse_metadata() }
-    default {
-        pod2usage(
-            -message => "invalid action '$action', aborting\n",
-            -verbose => 0
-        );
-    }
+SWITCH: {
+    if ($action eq 'add_account')    { add_account();    last SWITCH; }
+    if ($action eq 'list_accounts')  { list_account();   last SWITCH; }
+    if ($action eq 'add_service')    { add_service();    last SWITCH; }
+    if ($action eq 'list_services')  { list_services();  last SWITCH; }
+    if ($action eq 'add_token')      { add_token();      last SWITCH; }
+    if ($action eq 'get_token')      { get_token();      last SWITCH; }
+    if ($action eq 'list_tokens')    { list_tokens();    last SWITCH; }
+    if ($action eq 'parse_metadata') { parse_metadata(); last SWITCH; }
+    pod2usage(
+        -message => "invalid action '$action', aborting\n",
+        -verbose => 0
+    );
 }
 
 sub add_account {