chore: add license headers for REUSE license check

pineapple-pictures.pro

@@ -1,3 +1,7 @@
+# SPDX-FileCopyrightText: 2022 Gary Wang <wzc782970009@gmail.com>
+#
+# SPDX-License-Identifier: MIT
+
 QT       += core widgets gui svg
 greaterThan(QT_MAJOR_VERSION, 5): QT += svgwidgets
 
@@ -86,4 +90,4 @@ QMAKE_TARGET_COPYRIGHT = MIT/Expat License - Copyright (C) 2020 Gary Wang
 # MSVC only, since QMake doesn't have a CMAKE_CXX_STANDARD_LIBRARIES or cpp_winlibs similar thing
 win32-msvc* {
     LIBS += -luser32
-}
+}