support old cmake versions with finding boost

patch

@@ -0,0 +1,20 @@
+diff --git a/deploy/appimage/Dockerfile b/deploy/appimage/Dockerfile
+index 48b9ef7..51290a0 100644
+--- a/deploy/appimage/Dockerfile
++++ b/deploy/appimage/Dockerfile
+@@ -62,6 +62,8 @@ COPY ./*.h ./*cpp ./*.ui ./*.qrc CMakeLists.txt .
+ RUN mkdir build
+ WORKDIR /appimage/build
+ 
++RUN DEBIAN_FRONTEND=noninteractive apt install -y libboost-regex-dev
++
+ RUN cmake -DBUILD_TRANSLATIONS=on .. && make -j 8
+ 
+ WORKDIR /appimage/AppDir/usr/bin
+@@ -73,5 +75,4 @@ WORKDIR /appimage
+ RUN PATH=/usr/lib/qt5/bin/:$PATH linuxdeployqt --appimage-extract-and-run AppDir/usr/bin/checks-parser -no-copy-copyright-files -appimage
+ 
+ RUN mkdir -p /output
+-RUN cp Checks_parser-x86_64.AppImage /output
+-ENTRYPOINT bash
++ENTRYPOINT ["cp", "Checks_parser-x86_64.AppImage", "/output"]