Properly pad aliases for option usage

When printing the options of a command, options without aliases are
padded so they aligned with options with aliases The size of the padding
is calculated by multiplying the max number of aliases for an option by
the number 4 (a dash, a letter, a comma and a space?).

Options can have aliases of arbitrary length, not just just a dash with
a single letter. For example in Rails the `main` option has the [alias](https://github.com/rails/rails/blob/main/railties/lib/rails/generators/app_base.rb#L100)` --master`.
Also, the current implementation adds padding only to options without aliases.
This results in strange output when callings `bin/rails new -h`:

```console
  -T, [--skip-test], [--no-skip-test]                            # Skip test files
          [--skip-system-test], [--no-skip-system-test]          # Skip system test files
          [--skip-bootsnap], [--no-skip-bootsnap]                # Skip bootsnap gem
          ...
          [--edge], [--no-edge]                                  # Set up the application with a Gemfile pointing to the main branch on the Rails repository
  --master, [--main], [--no-main]                                # Set up the application with Gemfile pointing to Rails repository main branch
```

When printing the usage for options we should look at the actual
formatted options.

__Before (examples)__
```console
Usage:
  thor my_counter N [N]

Options:
  -t, [--third=THREE]   # The third argument
                        # Default: 3
          [--fourth=N]  # The fourth argument
  z, [--simple=N]
  y, r, [--symbolic=N]
```

__After (examples)__
```console
Usage:
  thor my_counter N [N]

Options:
  -t,   [--third=THREE]  # The third argument
                         # Default: 3
        [--fourth=N]     # The fourth argument
  z,    [--simple=N]
  y, r, [--symbolic=N]
```

lib/thor/base.rb

@@ -558,8 +558,7 @@ def print_options(shell, options, group_name = nil)
         return if options.empty?
 
         list = []
-        padding = options.map { |o| o.aliases.size }.max.to_i * 4
-
+        padding = options.map { |o| o.aliases_for_usage.size }.max.to_i
         options.each do |option|
           next if option.hide
           item = [option.usage(padding)]

lib/thor/parser/option.rb

@@ -93,10 +93,14 @@ def usage(padding = 0)
         sample << ", [#{dasherize('no-' + human_name)}]" unless (name == "force") || name.start_with?("no-")
       end
 
+      aliases_for_usage.ljust(padding) + sample
+    end
+
+    def aliases_for_usage
       if aliases.empty?
-        (" " * padding) << sample
+        ""
       else
-        "#{aliases.join(', ')}, #{sample}"
+        "#{aliases.join(', ')}, "
       end
     end
 

spec/base_spec.rb

@@ -139,8 +139,9 @@ def hello
     end
 
     it "use padding in options that do not have aliases" do
-      expect(@content).to match(/^  -t, \[--third/)
-      expect(@content).to match(/^          \[--fourth/)
+      expect(@content).to match(/^  -t,   \[--third/)
+      expect(@content).to match(/^        \[--fourth/)
+      expect(@content).to match(/^  y, r, \[--symbolic/)
     end
 
     it "allows extra options to be given" do