message: use custom target ALL to force building the appdata
diff: @@ -47,10 +47,6 @@ add_custom_command(
  COMMAND cmark_exe ${ACKNOWLEDGMENTS_MD} > ${ACKNOWLEDGMENTS_HTML}
  COMMAND cmark_exe ${PRIVACY_MD} > ${PRIVACY_HTML}
  COMMAND cmark_exe ${PLUGIN_MD} > ${PLUGIN_HTML}
  - COMMAND ${CMAKE_COMMAND} -DCHANGELOG_HTML:STRING=${CHANGELOG_HTML}
  - -DAPPDATA_CONF:STRING=${APPDATA_CONF}
  - -DAPPDATA:STRING=${APPDATA}
  - -P "${CMAKE_SOURCE_DIR}/cmake/generate_appdata.cmake"
  DEPENDS ${CHANGELOG_MD} ${ACKNOWLEDGMENTS_MD} ${PRIVACY_MD} ${PLUGIN_MD})
  # Add application library.
  @@ -93,6 +89,17 @@ add_executable(
  ${PRIVACY_HTML}
  ${PLUGIN_HTML})
  +if(GENERATE_APPDATA)
  + add_custom_target(
  + appdata ALL
  + COMMAND
  + ${CMAKE_COMMAND} -DCHANGELOG_HTML:STRING=${CHANGELOG_HTML}
  + -DAPPDATA_CONF:STRING=${APPDATA_CONF} -DAPPDATA:STRING=${APPDATA} -P
  + "${CMAKE_SOURCE_DIR}/cmake/generate_appdata.cmake"
  + DEPENDS ${CHANGELOG_HTML}
  + COMMENT "Create appdata file")
  +endif()
  +
  target_link_libraries(gittyup app)
  set_target_properties(
  