[vte] build: Fix libsystemd req version

[Christian Persch <chpe src gnome org>]

commit 81c7d901f7b3e9f961cb1113251a46af6d56b783
Author: Christian Persch <chpe src gnome org>
Date:   Wed Feb 5 18:27:22 2020 +0100

    build: Fix libsystemd req version
    
    sd_pid_get_user_slice() was added in 220, so change the minimum dep version to that.

 meson.build | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
---
diff --git a/meson.build b/meson.build
index 6963a19c..e3cc0b6f 100644
--- a/meson.build
+++ b/meson.build
@@ -45,7 +45,7 @@ gnutls_req_version        = '3.2.7'
 icu_uc_req_version        = '4.8'
 pango_req_version         = '1.22.0'
 pcre2_req_version         = '10.21'
-systemd_req_version       = '202'
+systemd_req_version       = '220'
 
 # API