mavsdk_tests: check installed version

Starting with MAVSDK 0.39.0 we can specify the version required. This
way we can fail at configure time instead of later during compilation or
linking.

test/mavsdk_tests/CMakeLists.txt

@@ -6,7 +6,10 @@ set(CMAKE_CXX_STANDARD 17)
 set(CMAKE_CXX_STANDARD_REQUIRED ON)
 set(CMAKE_EXPORT_COMPILE_COMMANDS ON)
 
-find_package(MAVSDK REQUIRED)
+file(READ MAVSDK_VERSION MAVSDK_VERSION)
+string(STRIP ${MAVSDK_VERSION} MAVSDK_VERSION)
+
+find_package(MAVSDK "${MAVSDK_VERSION}" REQUIRED)
 find_package(Threads REQUIRED)
 
 if(MAVSDK_FOUND)

test/mavsdk_tests/MAVSDK_VERSION

@@ -1 +1 @@
-0.38.0
+0.39.0