Add source files locally

With `target_sources` rather than referring to their path from another
directory.

Inst_eddies/Tests/CMakeLists.txt

@@ -56,9 +56,7 @@ target_link_libraries(test_nearby_extr Shapelib_03::shapelib_03
 
 # test_local_extrema
 
-add_executable(test_local_extrema
-  test_local_extrema.f90
-  ${PROJECT_SOURCE_DIR}/Tests/write_extr_map.f90)
+add_executable(test_local_extrema test_local_extrema.f90)
 
 target_link_libraries(test_local_extrema NetCDF95::netcdf95
   Jumble::jumble NetCDF_Fortran::netcdff)

Tests/CMakeLists.txt

@@ -4,3 +4,5 @@ add_executable(test_spher_polyline_area
 
 target_link_libraries(test_spher_polyline_area Geometry::geometry
   Contour_531::contour_531 Jumble::jumble)
+
+target_sources(test_local_extrema PRIVATE write_extr_map.f90)