Centralize Ruby Version to .ruby-version

The `.ruby-version` file is the ecosystem standard for defining a Ruby version.  This PR adds the `.ruby-version` file, ensures a `required_ruby_version` is set, and removes all other references to Ruby in this repository, aligning it with the standard.
> [!IMPORTANT]
> Please verify the following before merging:

Verify that the changes in the PR meets the following requirements or adjust manually to make it compliant:
  - [ ] `.ruby-version` file is present with the correct Ruby version defined
  - [ ] A `required_ruby_version` in your gemspec is set
  - [ ] There is no Ruby version present in the  `dev.yml` Ruby task (before: `- ruby: x.x.x`, after: `- ruby`)
  - [ ] There is no Ruby version/requirement referenced in the `Gemfile` (no lines with `ruby  <some-version>`)
  - [ ] A `Gemfile.lock` is built with the defined Ruby version
  - [ ] The version of Rubocop installed is 1.61.0 or greater
  - [ ] There is no `TargetRubyVersion` defined  in `rubocop.yml`
  - [ ] There is no Ruby argument  present in  `ruby/setup-ruby` Github Actions that do **not**  run on a Ruby matrix (no lines with `ruby-version: “x.x”`)

Please merge this PR if it looks good, this PR will be merged if there isn't any activity after 4 weeks.

.gitignore

@@ -2,7 +2,6 @@
 doc
 *.gem
 .bundle
-Gemfile.lock
 pkg/*
 vendor/
 tmp/*

.rubocop.yml

@@ -5,7 +5,6 @@ require:
   - ./lib/statsd/instrument/rubocop.rb
 
 AllCops:
-  TargetRubyVersion: 2.7
   UseCache: true
   SuggestExtensions: false
   CacheRootDirectory: tmp/rubocop

.ruby-version

@@ -0,0 +1 @@
+3.3.0

Gemfile

@@ -8,6 +8,6 @@ gem "minitest"
 gem "rspec"
 gem "mocha"
 gem "yard"
-gem "rubocop", ">= 1.0"
+gem "rubocop", "~> 1.61"
 gem "rubocop-shopify", require: false
 gem "benchmark-ips"

Gemfile.lock

@@ -0,0 +1,75 @@
+PATH
+  remote: .
+  specs:
+    statsd-instrument (3.7.0)
+
+GEM
+  remote: https://rubygems.org/
+  specs:
+    ast (2.4.2)
+    benchmark-ips (2.13.0)
+    diff-lcs (1.5.1)
+    json (2.7.1)
+    language_server-protocol (3.17.0.3)
+    minitest (5.22.3)
+    mocha (2.1.0)
+      ruby2_keywords (>= 0.0.5)
+    parallel (1.24.0)
+    parser (3.3.0.5)
+      ast (~> 2.4.1)
+      racc
+    racc (1.7.3)
+    rainbow (3.1.1)
+    rake (13.1.0)
+    regexp_parser (2.9.0)
+    rexml (3.2.6)
+    rspec (3.13.0)
+      rspec-core (~> 3.13.0)
+      rspec-expectations (~> 3.13.0)
+      rspec-mocks (~> 3.13.0)
+    rspec-core (3.13.0)
+      rspec-support (~> 3.13.0)
+    rspec-expectations (3.13.0)
+      diff-lcs (>= 1.2.0, < 2.0)
+      rspec-support (~> 3.13.0)
+    rspec-mocks (3.13.0)
+      diff-lcs (>= 1.2.0, < 2.0)
+      rspec-support (~> 3.13.0)
+    rspec-support (3.13.1)
+    rubocop (1.62.1)
+      json (~> 2.3)
+      language_server-protocol (>= 3.17.0)
+      parallel (~> 1.10)
+      parser (>= 3.3.0.2)
+      rainbow (>= 2.2.2, < 4.0)
+      regexp_parser (>= 1.8, < 3.0)
+      rexml (>= 3.2.5, < 4.0)
+      rubocop-ast (>= 1.31.1, < 2.0)
+      ruby-progressbar (~> 1.7)
+      unicode-display_width (>= 2.4.0, < 3.0)
+    rubocop-ast (1.31.2)
+      parser (>= 3.3.0.4)
+    rubocop-shopify (2.15.1)
+      rubocop (~> 1.51)
+    ruby-progressbar (1.13.0)
+    ruby2_keywords (0.0.5)
+    unicode-display_width (2.5.0)
+    yard (0.9.36)
+
+PLATFORMS
+  arm64-darwin-23
+  ruby
+
+DEPENDENCIES
+  benchmark-ips
+  minitest
+  mocha
+  rake
+  rspec
+  rubocop (~> 1.61)
+  rubocop-shopify
+  statsd-instrument!
+  yard
+
+BUNDLED WITH
+   2.5.3