ruby: Add support for running tests (#12052)

Hello, this pull request adds two things related to each other. I hope
it's fine to submit both in the same pull request but I am totally fine
with submitting them in separate pull requests, just let me know. This
is an initial version for both features. Thanks!

## Symbols outline support for testing frameworks: minitest and RSPec

Symbols outline support in
[Minitest](https://github.com/minitest/minitest) (the testing framework
that comes with Ruby on Rails out of the box) and RSpec (another testing
framework that is popular in Ruby and Ruby on Rails world). Here are
some screenshots:

### Minitest

Given this Ruby code:

```ruby
require "test_helper"

class CategoryTest < ActiveSupport::TestCase
  context "validations" do
    subject { build(:category) }

    should validate_presence_of(:title)
    should validate_length_of(:title).is_at_most(255)
    should validate_uniqueness_of(:title)
  end
end

class TestNamesWithMiniTest < ActiveSupport::TestCase
  def test_foo_1; assert true; end
  def test_foo_2; assert true; end
  def test_bar_1; assert true; end
  def test_bar_2; assert true; end
end
```

We have this symbols outline:

![CleanShot 2024-05-20 at 12 35
46@2x](https://github.com/zed-industries/zed/assets/1894248/c63a61d8-38cc-4969-a49b-dd9ce6920a0e)

### RSpec

I used `mastodon` application for testing because it's written in Ruby.
Given the following file
https://github.com/mastodon/mastodon/blob/main/spec/models/account_spec.rb
We have the following symbols outline:

![CleanShot 2024-05-20 at 12 44
42@2x](https://github.com/zed-industries/zed/assets/1894248/a754cf4c-f9cc-43f3-b365-1ce0ff942941)



## Running Ruby tests

### Minitest

Given the same file as above, we have the following workflow:



https://github.com/zed-industries/zed/assets/1894248/dc335495-3460-4a6d-95c4-e4cbc87a1ea0



### RSpec

Given the following file
`https://github.com/mastodon/mastodon/blob/main/spec/models/account_spec.rb`
We have the following workflow:



https://github.com/zed-industries/zed/assets/1894248/a17067ea-73b6-4229-8f1b-1b88dde63401

<hr />

Release Notes: Added Ruby test runnables support

extensions/ruby/languages/ruby/outline.scm

@@ -18,3 +18,9 @@
 (module
     "module" @context
     name: (_) @name) @item
+
+; Minitest/RSpec
+(call
+   method: (identifier) @run (#any-of? @run "describe" "context" "test")
+   arguments: (argument_list . (_) @name)
+) @item

extensions/ruby/languages/ruby/runnables.scm

@@ -0,0 +1,49 @@
+; Adapted from the following sources:
+; Minitest: https://github.com/zidhuss/neotest-minitest/blob/main/lua/neotest-minitest/init.lua
+; RSpec: https://github.com/olimorris/neotest-rspec/blob/main/lua/neotest-rspec/init.lua
+
+; Minitest
+;; Rails unit tests
+(class
+    name: [
+      (constant) @run
+      (scope_resolution scope: (constant) name: (constant) @run)
+    ]
+    (superclass (scope_resolution) @superclass (#match? @superclass "(::IntegrationTest|::TestCase|::SystemTestCase)$"))
+) @minitest-test
+
+(call
+    method: (identifier) @run (#eq? @run "test")
+    arguments: (argument_list (string (string_content) @name))
+) @minitest-test
+
+; Methods that begin with test_
+(method
+    name: (identifier) @run (#match? @run "^test_")
+) @minitest-test
+
+; System tests that inherit from ApplicationSystemTestCase
+(class
+    name: (constant) @run (superclass) @superclass (#match? @superclass "(ApplicationSystemTestCase)$")
+) @minitest-test
+
+; RSpec
+
+; Example groups with literals
+(call
+   method: (identifier) @run (#any-of? @run "describe" "context")
+   arguments: (argument_list . (_) @name)
+) @rspec-test
+
+; Examples
+(call
+    method: (identifier) @run (#any-of? @run "it" "its" "specify")
+    arguments: (argument_list (string (string_content) @name))
+) @rspec-test
+
+; Examples (one-liner syntax)
+(call
+    method: (identifier) @run (#any-of? @run "it" "its" "specify")
+    block: (_) @name
+    !arguments
+) @rspec-test

extensions/ruby/languages/ruby/tasks.json

@@ -0,0 +1,14 @@
+[
+  {
+    "label": "test $ZED_SYMBOL",
+    "command": "ruby",
+    "args": ["-Itest", "$ZED_FILE", "--name", "\"/$ZED_SYMBOL/\""],
+    "tags": ["minitest-test"]
+  },
+  {
+    "label": "rspec $ZED_SYMBOL",
+    "command": "./bin/rspec",
+    "args": ["\"$ZED_FILE:$ZED_ROW\""],
+    "tags": ["rspec-test"]
+  }
+]