Update output of bin/rails test -h in testing guide

Author: Earlopain

guides/source/testing.md

@@ -460,29 +460,36 @@ at the end of the test run and so on. Check the documentation of the test runner
 
 ```bash
 $ bin/rails test -h
-Usage: rails test [options] [files or directories]
+Usage:
+  bin/rails test [PATHS...]
 
-You can run a single test by appending a line number to a filename:
+Run tests except system tests
 
-    bin/rails test test/models/user_test.rb:27
+Examples:
+    You can run a single test by appending a line number to a filename:
 
-You can run multiple tests with in a line range by appending the line range to a filename:
+        bin/rails test test/models/user_test.rb:27
 
-    bin/rails test test/models/user_test.rb:10-20
+    You can run multiple tests with in a line range by appending the line range to a filename:
 
-You can run multiple files and directories at the same time:
+        bin/rails test test/models/user_test.rb:10-20
 
-    bin/rails test test/controllers test/integration/login_test.rb
+    You can run multiple files and directories at the same time:
 
-By default test failures and errors are reported inline during a run.
+        bin/rails test test/controllers test/integration/login_test.rb
+
+    By default test failures and errors are reported inline during a run.
 
 minitest options:
     -h, --help                       Display this help.
         --no-plugins                 Bypass minitest plugin auto-loading (or set $MT_NO_PLUGINS).
     -s, --seed SEED                  Sets random seed. Also via env. Eg: SEED=n rake
     -v, --verbose                    Verbose. Show progress processing files.
+    -q, --quiet                      Quiet. Show no progress processing files.
+        --show-skips                 Show skipped at the end of run.
     -n, --name PATTERN               Filter run on /regexp/ or string.
         --exclude PATTERN            Exclude /regexp/ or string from run.
+    -S, --skip CODES                 Skip reporting of certain types of results (eg E).
 
 Known extensions: rails, pride
     -w, --warnings                   Run with Ruby warnings enabled
@@ -491,6 +498,7 @@ Known extensions: rails, pride
     -d, --defer-output               Output test failures and errors after the test run
     -f, --fail-fast                  Abort test run on first failure or error
     -c, --[no-]color                 Enable color in the output
+        --profile [COUNT]            Enable profiling of tests and list the slowest test cases (default: 10)
     -p, --pride                      Pride. Show your testing pride!
 ```