fix

src/ruby/end2end/sanity_check_dlopen.rb

@@ -17,6 +17,7 @@
 # Some tests are flaking by failing to dlopen grpc. Perform some sanity checks.
 this_dir = File.expand_path(File.dirname(__FILE__))
 grpc_bin_dir = File.join(File.join(File.dirname(this_dir), 'lib'), 'grpc')
+grpc_c_sha256_path = File.join(grpc_bin_dir, 'grpc_c_sha256')
 grpc_c_so_path = if RUBY_PLATFORM =~ /darwin/
                    File.join(grpc_bin_dir, 'grpc_c.bundle')
                  else