[libsoup] build: Set environment for devenv

[Patrick Griffis <pgriffis src gnome org>]

commit fe62f18eb7646c7fe13ea9dbaf6e37a5da2e0d3a
Author: Patrick Griffis <pgriffis igalia com>
Date:   Sat May 8 19:49:15 2021 -0500

    build: Set environment for devenv

 tests/meson.build | 4 ++++
 1 file changed, 4 insertions(+)
---
diff --git a/tests/meson.build b/tests/meson.build
index 0892cccf..88c2813d 100644
--- a/tests/meson.build
+++ b/tests/meson.build
@@ -137,6 +137,10 @@ env.set('MALLOC_CHECK_', '2')
 # This is set by Meson if empty
 env.set('MALLOC_PERTURB_', '')
 
+if meson.version().version_compare('>= 0.58.0')
+  meson.add_devenv(env)
+endif
+
 if have_autobahn
    subdir('autobahn')
 endif