Update sqlite3 requirement from ~> 1.4 to ~> 2.0

Updates the requirements on [sqlite3](https://github.com/sparklemotion/sqlite3-ruby) to permit the latest version.
- [Release notes](https://github.com/sparklemotion/sqlite3-ruby/releases)
- [Changelog](https://github.com/sparklemotion/sqlite3-ruby/blob/main/CHANGELOG.md)
- [Commits](sparklemotion/sqlite3-ruby@v1.4.0...v2.0.1)

---
updated-dependencies:
- dependency-name: sqlite3
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <support@github.com>

Gemfile

@@ -21,5 +21,5 @@ gem 'shotgun'
 gem 'simplecov'
 gem 'simplecov-lcov'
 gem 'sinatra'
-gem 'sqlite3', '~> 1.4' # Ref: rails/rails#51592
+gem 'sqlite3', '~> 2.0' # Ref: rails/rails#51592
 gem 'webrick'