[cmake] Do not build the error estimation codes with differentiable c…

…lang.

We do not need to use a clad-compatible clang to build the error estimation
demos.

CMakeLists.txt

@@ -317,6 +317,9 @@ if (NOT CLAD_BUILD_STATIC_ONLY)
     include(GoogleBenchmark)
   endif(CLAD_ENABLE_BENCHMARKS)
 
+  add_subdirectory(demos/ErrorEstimation/CustomModel)
+  add_subdirectory(demos/ErrorEstimation/PrintModel)
+
   # Change the default compiler to the clang which we run clad upon. Our unittests
   # need to use a supported by clad compiler. Note that's a huge hack and it is
   # not guaranteed to work with cmake.
@@ -330,8 +333,6 @@ if (NOT CLAD_BUILD_STATIC_ONLY)
 
   add_subdirectory(unittests)
   add_subdirectory(test)
-  add_subdirectory(demos/ErrorEstimation/CustomModel)
-  add_subdirectory(demos/ErrorEstimation/PrintModel)
 
   # Add benchmarking infrastructure.
   if (CLAD_ENABLE_BENCHMARKS)