updates contributing.md

CONTRIBUTING.md

@@ -40,21 +40,9 @@ If you want to run tests for any of the languages {c, c++, node, php, python}, d
 
 `./tools/run_tests/run_tests.py -l <lang>`
 
-For list of available commands, refer to this:
-
-```
-run_tests.py [-h]
-             [-c {asan,asan-noleaks,basicprof,dbg,gcov,helgrind,memcheck,msan,mutrace,opt,stapprof,tsan,ubsan}]
-             [-n RUNS_PER_TEST] [-r REGEX] [-j JOBS] [-s SLOWDOWN] [-f]
-             [-t] [--newline_on_success]
-             [-l {all,c,c++,csharp,node,objc,php,python,ruby,sanity} [{all,c,c++,csharp,node,objc,php,python,ruby,sanity} ...]]
-             [-S] [--use_docker] [--allow_flakes]
-             [--arch {default,x86,x64}]
-             [--compiler {default,gcc4.4,gcc4.9,gcc5.3,vs2010,vs2013,vs2015}]
-             [--build_only] [--measure_cpu_costs]
-             [--update_submodules [UPDATE_SUBMODULES [UPDATE_SUBMODULES ...]]]
-             [-a ANTAGONISTS] [-x XML_REPORT]
-```
+To know about the list of available commands, do this:
+
+`./tools/run_tests/run_tests.py -h`
 
 ## Adding or removing source code