QtTest 3rdparty: isolate Catch2 part as a 3rdparty component

Move from tests/auto/testlib/selftests/ to
src/testlib/3rdparty/cache2/, so that its path includes a 3rdparty
component and it's isolated from the rest of the selftest files.
Instead, it's now grouped with QtTest's other 3rdparty components, to
make it easier, when doing a 3rdparty update, to see what might need
an update.

In the process, document where in the upstream to find the file to be
copied, if an update is needed. The file is generated, so document its
generator, too, in case its output gets renamed. There is no more
recent release than the 2.13.10 we currently have, so no update will
follow.

Task-number: QTBUG-126080
Change-Id: I371bac233b00318f59d6043fb245ab44b914bf8a
Reviewed-by: Jason McDonald <macadder1@gmail.com>
(cherry picked from commit 31adb73e289d1bd93276af2b1df9bc356ba14766)

src/testlib/3rdparty/catch2/qt_attribution.json

@@ -4,14 +4,16 @@
         "Name": "Catch2",
         "QDocModule": "qttestlib",
         "QtUsage": "Used for testing of the Qt Test module.",
-        "Files": "catch_p_p.h",
+        "Comment": { "UpstreamFile": "single_include/catch2/catch.hpp",
+                     "Generator": "scripts/generateSingleHeader.py" },
+        "Files": "catch_p.h",
 
         "Description": "Catch2 is a multi-paradigm test framework for C++.",
         "Homepage": "https://github.com/catchorg/Catch2",
         "Version": "2.13.10",
         "License": "Boost Software License 1.0",
         "LicenseId": "BSL-1.0",
-        "LicenseFile": "CATCH_LICENSE.txt",
+        "LicenseFile": "LICENSE.txt",
         "Copyright": "Copyright (c) 2022 Two Blue Cubes Ltd. All rights reserved."
     }
 ]

src/testlib/CMakeLists.txt

@@ -13,6 +13,7 @@ qt_internal_add_module(Test
     EXCEPTIONS
     SOURCES
         3rdparty/cycle/cycle_p.h # Needed by tests, so visible to syncqt.
+        3rdparty/catch2/catch_p.h # Also needed by tests.
         removed_api.cpp     # keep first
         qabstracttestlogger.cpp qabstracttestlogger_p.h
         qasciikey.cpp
@@ -79,6 +80,7 @@ qt_internal_add_module(Test
     PRIVATE_MODULE_INTERFACE
         Qt::CorePrivate
     ATTRIBUTION_FILE_DIR_PATHS
+        3rdparty/catch2
         3rdparty/cycle
         3rdparty/linux
         3rdparty/valgrind

tests/auto/testlib/selftests/catch_p.h

@@ -17,7 +17,7 @@
 
 #include <QtCore/qglobal.h>
 
-#include "catch_p_p.h"
+#include <QtTest/private/catch_p.h>
 
 QT_BEGIN_NAMESPACE