fix: Run strip_flags_binary test only for release configurations (#163)

diff --git a/test/CMakeLists.txt b/test/CMakeLists.txt
index 7e7fa86..4cd1e69 100644
--- a/test/CMakeLists.txt
+++ b/test/CMakeLists.txt
@@ -40,6 +40,7 @@
   NAME strip_flags_binary
   COMMAND "${CMAKE_COMMAND}" "-DBINARY=$<TARGET_FILE:gflags_strip_flags_test>"
           -P "${CMAKE_CURRENT_SOURCE_DIR}/gflags_strip_flags_test.cmake"
+  CONFIGURATIONS Release MinSizeRel
 )
 
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