McuSupport: Update test json files to new format

2.1 is released hence uses legacy creation of packages.
McuSupport refactoring is part of QtMCU 2.2.
Will be finished before qtc 8.
It will be documented before 2.2 and qtcreator 8.

Change-Id: Iab0e85f27186149cb73456983d15b30401d99233
Reviewed-by: Alessandro Portale <alessandro.portale@qt.io>

src/plugins/mcusupport/mcusupportsdk.cpp

@@ -480,7 +480,7 @@ static QList<PackageDescription> parsePackages(const QJsonArray &cmakeEntries)
     QList<PackageDescription> result;
     for (const auto &cmakeEntryRef : cmakeEntries) {
         const QJsonObject cmakeEntry{cmakeEntryRef.toObject()};
-        result.push_back({cmakeEntry["id"].toString(),
+        result.push_back({cmakeEntry["label"].toString(),
                           cmakeEntry["envVar"].toString(),
                           cmakeEntry["cmakeVar"].toString(),
                           cmakeEntry["description"].toString(),