Fix set not ignoring whitespace

Issue: https://tree.taiga.io/project/jktjkt-netconf-cli/issue/211
Change-Id: Ifc4e72c0c3b8ca4683cdcdf8262abfb1c58541b4
diff --git a/src/common_parsers.hpp b/src/common_parsers.hpp
index 8da90a6..71aedb9 100644
--- a/src/common_parsers.hpp
+++ b/src/common_parsers.hpp
@@ -32,7 +32,7 @@
     ];
 
 auto const space_separator_def =
-    x3::omit[x3::no_skip[x3::space]];
+    x3::omit[x3::no_skip[+x3::space]];
 
 template <typename CoerceTo>
 struct as_type {