Fix launcher spec for -v and --version to not depend on timings

Author: eregon

spec/truffle/launcher_spec.rb

@@ -81,12 +81,15 @@ def should_print_full_java_command(options, env: {})
   end
 
   it "does not create context on --version and -v" do
-    short = Benchmark.realtime { ruby_exe(nil, options: "--help:languages") }
-    version = Benchmark.realtime { ruby_exe(nil, options: "--version") }
-    v = Benchmark.realtime { ruby_exe(nil, options: "-v") }
-
-    version.should <= short + 0.5
-    v.should <= short + 0.5
+    v = ruby_exe(nil, options: "-Xlog=FINE -v", args: "2>&1")
+    v.should_not include("createContext()")
+    v.should_not include("patchContext()")
+    v.should include("truffleruby ")
+
+    version = ruby_exe(nil, options: "-Xlog=FINE --version", args: "2>&1")
+    version.should_not include("createContext()")
+    version.should_not include("patchContext()")
+    version.should include("truffleruby ")
   end
 
   it "preserve spaces in options" do