Tests: Enable Spreadsheet unit tests so they actually build

Author: https://github.com/bgianfo
Commit: adcd56473c
Pull-request: https://github.com/SerenityOS/serenity/pull/6727
Reviewed-by: https://github.com/linusg

Userland/Applications/Spreadsheet/CMakeLists.txt

@@ -38,6 +38,7 @@ set(GENERATED_SOURCES
 serenity_app(Spreadsheet ICON app-spreadsheet)
 target_link_libraries(Spreadsheet LibGUI LibJS LibWeb)
 
-# FIXME: build these tests
-#serenity_test(Writers/Test/TestXSVWriter.cpp Spreadsheet)
-#serenity_test(Readers/Test/TestXSV.cpp Spreadsheet)
+serenity_test(Writers/Test/TestXSVWriter.cpp Spreadsheet)
+
+serenity_test(Readers/Test/TestXSV.cpp Spreadsheet)
+target_sources(TestXSV PRIVATE Readers/XSV.cpp)