recipes: Stop passing --build-tool=ninja to compile.py

scripts/slave/recipes/findit/chromium/test.expected/none_swarming_tests.json

 [
   {
     "cmd": [
       "python",
       "-u",
       "RECIPE_PACKAGE_REPO[build]\\scripts\\slave\\kill_processes.py"
     ],
     "name": "taskkill"
   },
   {
@@ skipping 537 matching lines @@
       "--gsutil-py-path",
       "RECIPE_PACKAGE_REPO[depot_tools]\\gsutil.py",
       "--ninja-path",
       "RECIPE_PACKAGE_REPO[depot_tools]\\ninja.exe",
       "--target",
       "Release",
       "--src-dir",
       "[SLAVE_BUILD]\\src",
       "--goma-cache-dir",
       "[GOMA_CACHE]",
-      "--build-tool",
-      "ninja",
       "--compiler",
       "goma",
       "--goma-jsonstatus",
       "/path/to/tmp/json",
       "--goma-service-account-json-file",
       "C:\\creds\\service_accounts\\service-account-goma-client.json",
       "--goma-dir",
       "[CACHE]\\cipd\\goma",
       "--ninja-ensure-up-to-date",
       "--",
@@ skipping 97 matching lines @@
       "@@@STEP_LOG_END@report@@@",
       "@@@SET_BUILD_PROPERTY@report@{\"culprits\": {\"gl_tests\": {\"Test.One\": \"r1\", \"Test.Two\": \"r1\"}}, \"metadata\": {\"regression_range_size\": 1}, \"result\": {\"r1\": {\"gl_tests\": {\"failures\": [\"Test.One\", \"Test.Two\"], \"status\": \"failed\", \"valid\": true}}}}@@@"
     ]
   },
   {
     "name": "$result",
     "recipe_result": null,
     "status_code": 0
   }
 ]