Utils: Fix build with MSVC with C++20

Rename process.h back to qtcprocess.h

MSVC's "threads" standard header includes <process.h>, and that ends up
including our process.h from Utils.

There already was a hacky workaround in place for a similar issue with
MINGW, but that doesn't work with MSVC because that doesn't have

Simply use a name that doesn't conflict.

Change-Id: I1159cd2096b4f2dbc4a1728d0131dd6edd30ebd3
Reviewed-by: Qt CI Bot <qt_ci_bot@qt-project.org>
Reviewed-by: <github-actions-qt-creator@cristianadam.eu>
Reviewed-by: hjk <hjk@qt.io>

src/libs/utils/terminalhooks.cpp

@@ -5,7 +5,7 @@
 
 #include "externalterminalprocessimpl.h"
 #include "filepath.h"
-#include "process.h"
+#include "qtcprocess.h"
 #include "utilstr.h"
 
 #include <QMutex>