subprojects: valijson: Update to v0.4

v0.4 contains 66262bafb82c ("Include nlohmann/json.hpp instead of
json.hpp") which allows the valijson subproject to build correctly
against the nlohmann-json subproject.

Signed-off-by: Andrew Jeffery <andrew@aj.id.au>
Change-Id: I7af7c6a90f4bbd37ab1a737cf3625cf63cee342b
diff --git a/subprojects/valijson.wrap b/subprojects/valijson.wrap
index 736d202..577dd51 100644
--- a/subprojects/valijson.wrap
+++ b/subprojects/valijson.wrap
@@ -1,3 +1,3 @@
 [wrap-git]
-revision = c2f22fddf599d04dc33fcd7ed257c698a05345d9
+revision = 9183462118f58a3ca4be82b8f656f18707229737
 url = https://github.com/tristanpenman/valijson.git