Fix linking error when using cpprestsdk from apt (#26)

src/signalrclient/CMakeLists.txt

@@ -41,7 +41,7 @@ else()
     )
   elseif(NOT WIN32)
     target_link_libraries(signalrclient
-      PUBLIC ${CPPREST_LIB}
+      PUBLIC ${CPPREST_LIB} Boost::system
       PRIVATE OpenSSL::SSL
     )
   else()

test/signalrclienttests/CMakeLists.txt

@@ -24,5 +24,5 @@ include_directories(
 
 add_executable (signalrclienttests ${SOURCES})
 
-target_link_libraries(signalrclienttests gtest signalrclient ${CPPREST_LIB})
+target_link_libraries(signalrclienttests gtest signalrclient)
 add_test(NAME signalrclienttests COMMAND signalrclienttests)