Drive-by fix: Update two tests failing in --pass check mode

Author: petrochenkov

src/test/ui/json-multiple.rs

@@ -1,4 +1,5 @@
 // build-pass
+// ignore-pass (different metadata emitted in different modes)
 // compile-flags: --json=diagnostic-short --json artifacts --error-format=json
 
 #![crate_type = "lib"]

src/test/ui/json-options.rs

@@ -1,4 +1,5 @@
 // build-pass
+// ignore-pass (different metadata emitted in different modes)
 // compile-flags: --json=diagnostic-short,artifacts --error-format=json
 
 #![crate_type = "lib"]