hardcode build rpath to see if this is the problem

Author: finagolfin

Sources/Foundation/CMakeLists.txt

@@ -159,6 +159,7 @@ if(CMAKE_SYSTEM_NAME STREQUAL Windows)
     $<TARGET_OBJECTS:CoreFoundationResources>)
 elseif(NOT CMAKE_SYSTEM_NAME STREQUAL Darwin)
   target_link_options(Foundation PRIVATE "SHELL:-no-toolchain-stdlib-rpath")
+  set_target_properties(Foundation PROPERTIES BUILD_RPATH "/home/buildnode/jenkins/workspace/swift-corelibs-foundation-PR-Linux/buildbot_linux/swift-linux-x86_64/lib/swift/linux")
 endif()